How to research strength of out of town rental market

[MA Efron]

Is there anywhere to go for data on how quickly homes rent in particular rental markets?

I've been interested for some time in investing in rental properties in an area I'm very familiar with, but I no longer live there. The numbers look okay to me, but before I take the plunge, I want to find out how quickly homes rent in the area - don't want my investment sitting empty for months.

I've watched the area's Craigslist listings, for repeats, and a local management company's listings online. Of course the management company assures me that rentals go quickly in the spring and summer, but I like hard data. Is there anywhere to go to research this?