Forgot to mention, for 3 months the best would be searching for apartment sublease or taking over a lease, from someone wanting to leave but the contract is not up yet. The usual goodies are one month free or waiving the deposit the original leaser put down.
Or if you are looking for a room only the rent is usually around $450-700 for a room (700 is master). Whole apartment rent is around $1000 for studio to $1600 for 2 bedroom luxury new apartment, something like that. Craigslist is the best guide.
The only thing it can get better for sunnyvale IMO is the school. It is not as good as the surrounding cities like Cupertino or Saratoga, therefore the homes aren't as expensive. It is still decent up to HS, the HS is average to above average, but not top 10 of the nation like Cupertino or Fremont.