Found this info. Interesting... The real estate fideicomiso prior to 1998 used to be for 30 yrs, so if it was established in LC in 1986 it would expire in 2 yrs. Why would one chose to renew in a master trust? For the time, money, hassle spent renewing the master why not convert to an individual trust?
A Real Estate Fideicomiso is irrevocable ownership set in 50-year increments, perpetually renewable, and is transferable. There is only one Real Estate Fideicomiso, however, and it is offered in two forms: Master Trust or Individual Trust.
Master Trust:In this type of Trust, a master umbrella Trust is formed and the individuals own a piece of the Master Trust. The Master Trust holds all the properties and makes all decisions regarding the Trust/property. It is responsible for, and pays the taxes on the entire property held within the Trust and appropriates amounts for reimbursement from the individual owners. The risk in a Master Trust is if the Trust property should incur a lien or judgement against it, what affects one affects all. Whoever controls the Master Trust holds tremendous power over it. The beneficial aspect of the Master Trust is that it is less expensive to set up and maintain.
Individual Trust : In an Individual Trust each property owner owns, maintains, and is responsible to pay taxes on their own Trust/property. It is slightly more expensive but the security of total control over your own Trust/property is worth the small additional expense.
http://www.northernbajarealestate.com/Buying_in_Mexico/page_1886210.html
http://www.bajaopenhouse.com/Fideicomiso_-_Bank_Trust/page_1922035.html