Some weeks back I received a flyer about a network of families that take care of animals in their own homes - I kept it in case I ever need it myself. I don't know any more about them than what is on the flyer, so this is not a personal recommendation. But you could investigate for yourself.
No website was given, but the Facebook page Olivia Andrealli was given, and the hotmail address is the same name (no spaces, no .ar). Also a cel 15-5842-6627.
They require evidence of vaccinations, etc. They also note that you can check/talk to your dog or cat over skype when you are away.
They also look after fish, birds and plants - presumably in your casa.
Hope this is helpful, and that if you investigate further you share what you find with the rest of the pet people on here.
La Fleur