Rental Property Research
Where is in the U.S. would I find the best balance of Cap rate (cap rate is the net operating income divided by the cost of a property), appreciation, and vacancy rate?
Alternatively, where can I go to find such information?
You do not define your criterion for "best". You can find appreciation by doing a google search on HPI (Housing Price Index) and OFHEO to get government data on housing price increases by MSA (Metropolitan Statistical Area). You can get Cap rate data from the sites that have properties for sale. For vacancy rate info I suggest that you contact property management companies in the areas where the other two statistics are to your liking.