Speaking of cheap rent, I'm in São Carlos for a few days and it seems awesome for startups. I'm considering moving here.

Off topic: actually, I'm here due to a thread about the city you started on HN some months ago! I have some more questions about how São Carlos has worked out for you - if you'd be free to meet and discuss, please email me (I can't find yours anywhere unfortunately):

charles dot offenbacher at gmail dot com