Sales and service receipts, in order to be used legally as a tax write-off (known as "facturas"), must be laboriously created and accounted for each time a transaction is made---because the system is so cumbersome and costly, most businesses work within the more common underground economy that works on a "cash" basis and therefore avoids taxation whenever possible. 

Many business processes are not tax write-offs, such as entertaining a client, purchasing products or services in the US for use in Mexico, etc..

Accounting and tax reporting laws are so severe that businesses often have to hire 3 separate accountants or accounting companies to comply: one to prepare the books, another to check the books, and still another to verify the other two accountants---otherwise, one small mistake could result in the company being forfeit to the Mexican government (under its laws).

Employment laws are very convoluted, requiring legal specialist and specialized contracts to keep employers from having to pay employees, particularly ones they fire, large sums of money as penalties. Such antiquated employment laws may it difficult to hire and use the Mexican worker in their own country.

The average Mexican worker in Mexico earns between $50 and $100 per week (the workweek is Monday through Saturday--half day on Saturday, 45 hour min. workweek). In the US, the average illegal worker earns between $50 and $75 per day for 8 hours work.

Most Mexican investors refuse to invest their money in Mexico due to safety and security issues, choosing, instead, to invest in other countries, such as Spain, Europe, and the US.

Mexico routinely tries to borrow money from the US and other countries to provide themselves with much needed infrastructure.

Investments in Mexico are subject to high risk of loss. With organized crime entrenched throughout Mexico and its most lucrative industries and government, legitimate companies often find themselves compromised by racketeering or kidnapping schemes, which can siphon off most or all of a company's treasure and put undue stress on working executives or company heads and their families operating and living in Mexico.

Key executives and family members are often targets of kidnappers. It is not uncommon for victims to have body parts removed or be killed even if ransoms are paid.

Percentage rates are often triple or higher than those paid in the US when borrowing money for business or real estate.

Few people or businesses qualify for loans.

Mexican inflation rates are often triple or more than those found in the US (historically).

Farmers and manufacturers, particularly in southern Mexico, often hire illegal alien migrants (from Nicaragua, Guatemala, etc.) who will work for less wages than they have to pay their Mexican citizen workers, often displacing hundreds of thousands of Mexican workers while abusing the slave-like labor of illegal aliens (sound familiar?).

The practice of "free trade" has destroyed Mexico's small-farm  industry and displaced millions of farmers who once earned a living on their small acreages of land for themselves and their families.

Crops are routinely given pesticides that are banned in the US - even though foods from Mexico are exported into the US.

Mexico's air pollution is among the worst in the world. In Mexico City, it is not uncommon for visitors to report burning and stinging eyes just hours after arriving; those with repertory problems are told to avoid Mexico City's air.

Lake Chapala, the nation's largest lake, has been essentially killed due to industrial pollution that is routinely poured into the lake from adjoining factories on its shores (typically throughout the industrialized parts of Mexico).

Raw or untreated sewage from towns and cities are routinely dumped into nearby oceans and seas, ensuring that most population centers have high levels of toxins and bacteria harmful to humans in their recreational or resort waters.

Although toxic chemical dumping is technically illegal in Mexico, it is not uncommon (when caught, business owners simply pay authorities small bribes to look the other way).

Except for portions of land extending beyond about 67 miles inland from the coast and waterways, most real estate can not be owned by Americans (or foreigners), except through a bank trust (and banks have been known to break the trust and transfer land ownership to others, leaving the original foreigner or American owner with nothing).

Mexican court systems rarely uphold legal cases brought forth by Americans or foreigners.

Real estate law in Mexico recognizes that anyone may hold a claim to land ownership even though they are not on public record, which means that unscrupulous (or legitimate) operators may make claims against your real estate purchase, even years after the fact, and effectively take ownership through the court system. There is no "Quiet Title Action" available in Mexico to ensure against this happening.

Courts can take up to 15 years to process real estate claims, effectively rendering the property unusable during a strong legal action. Unscrupulous business competitors may enjoin your property toward stalling your commercial progress toward ensuring their own.

It is not uncommon for unscrupulous operators to use laws regarding abandonment and vacancy to their favor to win legal ownership of real estate assets: For example, if an absentee foreigner purchases a home then leaves for long periods of time (6 months or more) they may ultimately return to find they are no longer the property owner. The process works by the unscrupulous Mexican simply filing abandonment proceedings, providing false witnesses and taking possession through the courts during the absence of the owner).

Nobody, particularly Americans, may receive medical services unless they are paid for in advance (this includes life and death emergencies, such as when someone is bleeding to death).

Less than 20% of the Mexican population is covered through employers paid government healthcare programs, and when care is offered, it is often substandard and dramatically minimal.

Medical malpractice is not a major legal aspect for doctors in Mexico so often those who have committed egregious medical negligence in the past are not barred from further medical practice.

Equipment and training for doctors and dentist in Mexico is considered several decades behind that of the US in terms of development and practical applications.

None exist in Mexico.

The Mexican government does provide for government housing but the projects are rare and the cost reductions often insignificant while the waiting list highly corrupted.

Mexicans must pay for their children's education at every level.

Many Mexicans in border areas avoid paying for their children's education by commuting them across the border daily to attend free schools in the US.

Only Mexican citizens can vote or have a political voice. Any person who immigrates to Mexico and who is not considered a birthed citizen of Mexico, is prohibited from voting.

Public activism and anti-government displays are not legal in Mexico and often not allowed and quelled with violent police action.

Foreigners, such as Americans, are not allowed to protest in the streets ever. 

It is crime to criticize the Mexican president or their cabinet.

Mexico has had a long history of voting issues with many allegations of system fraud.

Trespassers on Mexican soil are often shot at, beaten, raped, murdered, robbed, and imprisoned with little food or water.

Americans found to be in Mexico illegally are fined. Those failing to pay the fine are immediately deported and barred from return.

About every 500 yards (in the most frequented areas) there are towers with machineguns, which are legally able to shoot to kill any would-be trespasser.

Posted along the border are signs that read (in essence), "use of deadly force authorized if you trespass onto Mexican soil."

Hundreds of illegal aliens are wounded and some killed every year along these border areas.

When an American calls the police to report a crime, the standard procedure for the police is to side with the Mexican citizen that is accused of the crime---Mexicans are rarely arrested for crimes against Americans and are often let go on the way to the police station.

Jurisdiction---Mexican law enforcement loves to send Americans on a wild goose chase from state, to federal, to city, and other law enforcement agencies when a crime has been committed, particularly car theft---rarely do they want to take a report or catch a criminal on behalf of an American victim.

Many Mexican citizens refuse to report crimes like kidnapping, murder, drug trafficking, car theft, and other crimes because of the an entrenched cultural norm and understanding that laws are optional and that the police are most likely  involved with the criminal affair--often working hand in hand with organized crime in the area.

Few Mexicans are willing to provide witness statements or court witnessing for many crimes, as they feel their lives and their family's lives may be put in danger by law enforcement officials working in conjunction with organized crime.

Police are becoming more criminally embolden, often stripping a person of their identification documents and money prior to or upon arrest---those confronted never see their possessions again---an illegal practice in Mexico but not investigated or prosecuted.

Mexico ranks as one of the highest countries in the world statistical for the murder of its investigative journalist.

An estimated 2/3 of all police in Mexico are considered corrupt and are often also on mafia payrolls (police are paid about $150 a week in Mexico, hence they are easily driven toward corruption in order to supplement their paychecks).

Due to the immense and generational-sustained poverty in Mexico, the Mexican government has conducted research and concluded that the average Mexican believes it's okay to take things that do not belong to them. From 1999 to 2004, the Mexican government has held public relations messages across the country on television attempting to educate its people into "unlearning" this societal norm. [One research study turned into a public service message showed 10 out of 10 Mexicans (men and women) entering a restroom and stealing a single new bar of soap left on the counter].

As an American, if you have to use a lawyer, you may be in for for a costly ride. It is not uncommon for most lawyers to be generalist, proclaiming to be specialist in the area of law that you need help in. You will, likely as not, find yourself bouncing from lawyer to lawyer with  your checkbook ringing off the hook as you seek the quality assistance you need to solve your legal problem (but usually will never find).

Forget bringing a lawsuit---it's common practice for lawyers to make backroom deals with your adversary and then turn around and use creative ways to dissuade you to drop the case---often telling you your hopes are lost or simply delaying until you lose interest.

All legal documents are in Spanish only (the law does not recognize any language but Spanish).

All business documents and services are in Spanish only (no courtesy English alternatives).

All education to children is strictly taught in Spanish (except second language classes).

Few Mexicans beyond the border regions and tourist centers speak a foreign language like English.

Most illegal aliens in the US only speak Spanish.

Most homes in Mexico must have unsightly security bars over their windows, as home break-ins are a major and common concern for all residence.

Petty and violent crimes are on the rise in Mexico, particularly against the middle-class who are perceived "to have money." (Crimes include, car jacking, robbery, rape, murder, battery, and more).

Car theft and break-ins in areas or businesses where Americans gather is typically very high.

Many malls, although they have security toll booths and limited access, are often the primary targets of organized crime rings for car theft.

It is common practice to be pulled over by a police officer and rather than pay a traffic ticket, pay a "mordida" or bribe if you are a foreigner.

It is not uncommon for some business owners to make backroom deals with local crime gangs that allow the gangs to routinely steal or break into autos when at the business location.

Guns are used in most violent crimes against both Americans and Mexicans even though guns are essentially illegal in Mexico (criminals have no problem getting guns, including machine guns, in Mexico). Law abiding citizens are typically unarmed and therefore considered easy targets while those who have armed bodyguards are rarely attacked in comparison.

Most murders in Mexico are by gun death even though guns are all but illegal in Mexico.

Mexico now ranks as one of the world's leading countries for kidnapping, business extortion, and money laundering.

Along many border areas, hate crimes against Americans are increasing due, many claim, to immigration enforcement and border security policies in the US (some even perpetrated by Hispanic gang members from the US who travel south of the border).

Mexico applies a unique caste system: Native Indian descendants are considered the lowest class, next are foreigners and those of foreign races (i.e. Asians, Blacks, Germans, Canadians, Americans, etc.), the next class level is the Mestizo (Indian-Spanish descendants) who make up the vast majority of the country's population, and the top rung is held by the Euro-white class (typically Spanish or French descendants) who make up most of the aristocracy of Mexico (about 12% of the population).

Each class looks down harshly on the next class in Mexico and discrimination is very normal.

Mexico has never underwent the pains of learning from a Civil Rights movement, hence racism remains very high in the Mexican culture (as it does with most Latin countries).

Some areas throughout Mexico are experiencing a labor shortage of trained workers (i.e. construction, manufacturing), as most have left to the US to work illegally.

It is well known throughout Mexico that nearly anyone can hire a murderer or even a team of murderers for as little as one thousand dollars per murder (many newspapers have reported that police chiefs and other high ranking officials have been murdered for less than $10k using 10 assassins). This fact alone makes working in Mexico for foreigners a much more difficult and dangerous endeavor.

The murdering of news reporters is so common in Mexico it has become a mundane subject. Reporters are virtually unable to trust anyone they come in contact with it the sectors of authority.

Mexico harbors many American criminals as well as Mexican ones. It is not uncommon to hear that your neighbor, or someone you have met, is wanted on the other side of the border by law enforcement.

Mexican police often shake down American criminals in order to increase their own personal income, and in exchange, allow the criminal to remain in Mexico undetected. 

Organized crime plies its trade of money laundering by often seeking  legitimate business owners out, particularly the large ones, to press them into service under the threat of violence. 

Those who refuse are murdered or have their family members kidnapped until they submit.

The police cannot be called in as they are often involved in the criminal activity, leaving the otherwise law abiding Mexican business owner at the mercy of the criminals.

Your house can be broken into at any time by your local neighborhood locksmith. (Although there are laws against the practice, in practicality, anyone can hire a locksmith to come to somebody's house, change the locks, and thereby enter the house at will and with impunity).

Prejudice, although mild, is normal against Americans who are often viewed as a necessary evil with wallets full of money. It is not uncommon for Mexicans in the border areas  to speak ill of an American (in Spanish) who might be sitting next them in public.

As an American, be prepared to be charged a lot more for goods and services than Mexicans---a clear double standard is in full operation in most places along the border and tourist areas of Mexico where Americans are found.

As an American, freedom of speech is not something guaranteed in Mexico and many things that might be allowed in the US could land you in jail or subject you to charges of slander. 

US law enforcement and other government agencies are increasing the amount of information on US citizens that they give to Mexican officials.  As the Mexican standards for preserving the security of information is all but non-existent, the information, when possible, is commercialized into criminal activity and is often sold or given to criminal organizations.

Kidnappers often "grab" bank employees in Mexico and force them to print customer lists showing the balance in personal and business bank accounts so they can identify lucrative kidnapping targets.

The same techniques are applied to government officials and administrators in order to obtain sensitive information on individuals, such as assets owned, number of children, addresses, and more. 

The average business owner in Mexico tries to operate as best they can, in a legal and respectable manner comparable to the US.

Many businesses are operated by family and extended family members.

Most agreements with the customer are honored.

Customer service is not on a par with the US - the operator and its employees typically maintain a "take it or leave it" attitude (and is often uneducated as to modern business practices used by Americans in service related industries).

Most parents try to instill a strong moral and religious behavior in their children.

Family units are typically strong and the divorce rate, although low, is now beginning to rise in Mexico.

Sunday is the traditional day of rest, relaxation, and celebration for families. It is not uncommon for the male Mexican worker to get inebriated on this day.

The Christmas holiday season is considered the single most important time of the year for the Mexican family, as it represents a time of rest, relaxation, seeing extended family members, worshipping, and celebration---so important to most that they will not hesitate to leave even a great job to participate in this 2-3 week annual tradition.

Mexico has one of the most diverse ranges of scenery on the planet, from jungles in the south to deserts in the north and thousands of miles of beaches dotted with resorts and friendly service attendants.

Historical sites throughout Mexico make it one of the richest cultural countries in the world, including Toltec monuments, to pyramids, to colonial buildings of government and more.

Tourists used to be generally safe and treated well in many tourists areas, as the local governments had generally kept a strong eye on tourist focused crime or take aggressive steps to protect tourism reputations but this increasingly not the case today. Today, an alarming trend toward tourist kidnapping is occurring throughout Mexico, with particular focus on the border areas (most of these crimes go unreported and are not shown in crime statistics with either the FBI or the Mexican government).

Most crimes against tourist are classified as minor when they do occur and are not unlike those encountered in most countries. However, a growing trend of hate crimes against Americans has been registered by many newspapers and even noted by the US Consulate who is now issuing travel warnings for Americans visiting or living in Mexico.