Another site to check out market rent is Zillow. Now they provide rent estimate.
My two cents on your choice of location. The price for an entry level SFR in Saratoga starts at mid $700's and that's not even in the Saratoga school district, compared to only mid $400's for Campbell. You will find that your return for an investment property will be better in Campbell. Beware that Campbell school district has good schools and not so good schools. Pick one that's in the better school area. If you need help on that, I will be happy to assist. Another area I would recommend is Cambrian, San Jose, which is just east of Campbell. They have good school and the starting price is also in the $400's.