According to the new law, there will be different types of migratory documents that authorize you to work in Mexico. There will be a six month migratory document which allows you to work as a visitor, there will be a temporary resident card which allows you to work and can be valid up to four years (though they are somewhat vague about this, I suspect it will be four years with yearly renewals) and there will be a permanent resident status which can allow you to work as well.
i just went in (PdC) yesterday and it is still possible to do on your own but you'll need Spanish (course you should already speak it living here and all). I didn't need bank statements but the cambio de caracteristica for my son did (gave April and June). Needed the solicitud and the solicitud has totally changed from last year. They are looking for specific wording that you will find on your prorroga sheet. Needed photocopy of my FM3. I always do about 3 copies of everything anyway. I also gave landlord letter (not sure if it was necessary or not) and the application form. They specifically ask for: 1) internet application 2. original and copy of pasaporte. 3. FM3 original. 4. Solicitud with specific wording "bajo protesta de decir verdad manifesto que subsisten las condiciones bajo las cuales me fue concendida la caracteristica migratoria" and then you specify how. 5. your last payment (if you're working). I wasn't asked for bank statements. 6. if you're religious, have a lawyer, etc. more conditiones.
