Better make sure the hotel is actually built before going there. The thieving kids in the parks are just waiting for the tourists to show up. Still amazed that Rio was actually picked as a host town, it has FIFA ethics written all over the "deal". Thinking it's going to be a disaster.
I am sure you can find a barrio to stay in for a few weeks really cheap. The trick would be convincing the locals that you are not a rich tourist and avoid getting mugged. Fluency in Portugese would help.
Why go to Brazil and not got to Jeri instead? You can watch the Olympics on TV at night.