Where's the cheapest hostel or place to stay in Piracicaba, Brazil?

Help!! I'm heading to Brazil TOMORROW to start a volunteering program in Piracicaba, Brazil and my housing arrangements got changed at the last minute. My new host family won't be ready for me till Monday and right now it's too expensive to change the flight arrival times, so I've decided to just arrive anyway and stay somewhere for 3 nights. I am taking a bus from the airport in Sao Paulo to Piracicaba. Where's the cheapest place to find a room???