Looking for a room in Sampa: March 23-May 1

Hi,

I'm a Dutchman in his early 30s soon going to visit Sampa/o Brasil for the first time, because I've met some nice Brazilians abroad, read some great Brazilian poetry and literature in translation, and heard good stories about the country and culture for a long time now. My stay in São Paulo city will be from March 23 until May 1.

I'm looking for a small room (incl. bed, use of bathroom, possible use of a (shared) kitchen) in one of the more centrally located neighborhoods, preferably Pinheiros. It may cost anything up to about R$ 1200.
Either a room for the full period, or for the month of April alone. For that final week of March I can find places via CouchSurfing.

I've tried to find a room to sublet/rent through craigslist, and looked at AirBnB (expensive if you're staying longer), but until now I haven't been able to find an affordable room for the period I'm gonna stay in SP.

Any help would be much appreciated.

kind regards,
taco