How are the economic forecasts of the area?

I am trying to select a market with a strong economic anchor. 

Mortgage impound account is ~950$Rental turnover has been less than a month for each property in the 2 years and I'm confident if there is a economic downturn/recession they will still be rented.

The economics of this city is based off of fishing/oil and gas. 

I think NE dc or like PG county would be SUPER interesting..and have a huge economic effect on real estate but also the communities, businesses, and transit...

So since I'm looking at Houston, San Antonio, and Orlando areas suburbs it is not a total deal breaker assuming it's not too far from city/economic anchor and commuting to work is a norm.

I've also been told that vacancy rates on a 3 bedroom apartment are actually higher than a 2/2 - so the reality might be that going 3 bedroom would actually be worse off economically once you factor that in. 

As somebody who wants to step into the rental market myself (though likely not in CO), I plan to ease in with just one unit at first, cash, and add more at a rate no faster than 1 additional unit every six months, knowing full well we're likely to be in the later innings of what's been a lengthy economic expansion. 

Most importantly, does any of these submarkets have any economic anchors  like state government, major universities, major health care centers, or manufacturers that are independent of the economy like military suppliers that employs most of the residents of that submarket?

All of this is with me running a 10% vacancy (plus the additional economic vacancy created from me not paying market value for my unit), 30% for operating expenses, and at the asking price.