Selling first home, buying new primary residence.Invest the gain?

[Kolt Johnson]

Hi everyone, 

My wife and I are in our early 20's and are under contract on both the sale of our house and the purchase of a new primary residence. We are going to make a good gain on the sale of the current home after all expenses get paid for the new house. We want to get into long-term rentals but have no clue where to start. I stumbled across the BP podcast a few months ago and have been addicted ever sense. What is a good way to evaluate properties that are potential investments? TIA!