I don't know about you Tom, but since we talked about some of the challenges of foreign purchases, including potential inexistence of Title Insurance, I have gotten a number of PM's about how I dealt with that in Brazil. Another challenge to purchasing here: the inexistence of Escrow Accounts!
So you either have to: open your own account here (tough to do if you're not a resident), trust the seller and just wire the funds directly (good luck with that), bring your funds down (not recommended), massively use the local ATM's (if you have lots of time, like months, to spare and are preferibly in the trusted company of good security), or directly negotiate with (and trust) the seller's bank not to release funds until all purchase requirements have been met.
For your Mexico purchase, were you able to use some type of Escrow arrangement to get funds to the seller?