Hotels in Brazil can be priced all over the board. The country is huge, and depending on the season, location of the city, and events in the city, pricing could seem extremely high, while a neighboring city might be bargain basement priced! Even just a different section of the city might be all it takes to find great deals on hotels.
Cities like Rio will often have wide ranging prices on hotels, due to number of events that take place there. From general conventions, to summer beach travelers, to the Carnival festivals. Sao Paulo on the other hand is considered a business city, and has fewer tourists, but far more business travelers. Due to the sheer size of Sao Paulo, a convention will unlikely change the majority of the hotel prices, but could loosely effect pricing around the event. If prices seem to be unusually high, try moving your dates around by just a few days. You may have just unwittingly picked travel dates over top of an extremely busy period.
We have built out our hotel section to include many hotels, each with linked to a booking agent to keep things simple. Each booking site has additional information on the hotels, and even neighboring hotels which might be of interest.