Freedom,
I don't use GRM calculations.... Plus I am purchasing close to the beach. In talking with most rental agents as well as looking at the rental history, any place close to the beach has been a very desirable place. Unfortunately purchasing land there usually expensive, hard to find or both. I am kinda lucky.
I also price my properties somewhat lower to keep the renters happy as well as keep the vacancy down. I do understand what you mean about the dropout we had with engineers here in the area. It was bad, but I also think things won't get that bad. But we will see.
-bix