Data Sources - Price of Property Over Time?

[Dan Talmi]

Hi everyone, 

I'm trying to determine a realistic range of asset appreciation or reduction in value over time on prospective multi family properties. I KNOW that this information must exist. Where do you all look for this type of data? Is it really reserved for paid services? Any tips on where the most reliable data on property values over time, rent values over time etc would be greatly appreciated! For reference, I'm in the Albany NY market. 

Thank you,

Dan