There are two things you need to know about "Brechos" in Sao Paulo before you spend time looking…read morefor treasures from a different time period.
1.) Maybe half of what you see is for sale.
Brechos collect vintage clothes and accessories and rent them out. I went into Arca da Vila and saw a nice yellow belt. When I asked the cost of it she said it was only for rent. 15r a day. How these places stay in business is beyond me.
2.) There's always a jeito.
If you really, really love something that's not for sale there's a possibility you can buy it. For a price. This yellow belt I mentioned earlier for example was offered to me for 70r. It's an old, plastic belt. Come on girlfriend, work with me.