Rental rate historical data?

[Casey Miles]

Is there a source (website) where I can research rental rate data? I rarely raise rents in my units and usually wait until a vacancy occurs, research rental rates via craigslist, etc, and then rent for whatever the market will bring.

I recently bought a duplex where the previous owner raised rents almost annually by 2.5-3 percent each time. Obviousely it depends on the market but what does everyone else do? Scheduled increases? Wait for vacancies?

I'm in the Phoenix market and have both MF and SF.

Thanks everyone,

Casey