Mexican rental markets have very few regulations, so the terms of your rental contract can be open to negotiation. However there are some common terms that should serve as an indication of what is acceptable and what is not.
Rental contracts come in all lengths, but many contracts require a minimum rental period of 12 months with an automatic extension and a one-month notification period for terminating the contract (for both parties). In tourist areas you will find many short-term rentals as well, though these tend to be more expensive than normal contracts.
After the minimum period, your landlord can cancel the contract at any time without having to legally justify this decision. If rental prices increase in an area you should be prepared to be asked to pay more rent or leave the property.
Most landlords demand a deposit of equal value to a month’s rent which has to be paid together with the first month’s rent and will be returned to you if you leave the apartment in its original state. When moving in, you should insist on an inventory which states all items in the accommodation (including kitchen supplies and furniture) and any defects that might already exist.
Some landlords also ask for an aval (a financial guarantee) from a third person or a bank, although this requirement is often dropped when dealing with a foreigner.
Your rent has to be paid either directly to the landlord or to an agency (if you used one). As automated bank transfers are still relatively uncommon, many landlords will pass by to collect the rent in cash or will ask you to hand it over at their office or agency. You should insist on a receipt for each payment.
Make sure that you understand all parts of your contract. If in doubt, ask a friend or an agency to translate it for you. Be aware that even if there is an English version of the contract, only the Spanish version will be recognized by law.