How to forecast the future economy of a market

[Aaron Keckley]

I have finished reading The ABC's of Real Estate Investing by Ken McElroy. In his book, as well as in the BP podcast he is in, he discusses that the preliminary research of any real estate investment isn't a property, but the surrounding market that a property is located in.

My question is: What resources have you found most helpful in forecasting the future economy of a market or submarket? And, how do you recognize through all the information you may find, the data that really matters?