On the buy and hold side I put some classic of landlord lit in my blog (all older books that should be free in the Bellingham libraries for an economical start)... 

My 10-year Real Estate Development career began as I served as Co-Chair of the Economic Development for the Over-The-Rhine (OTR) Planning Steering Committee.

Can anyone suggest where this can be done economically?  

It does not always follow economic data- and certainly not the stock market.

I would look for an area that has good economic job prospects but a shortage of housing.

http://www.frbsf.org/economic-research/publications/economic-letter/2015/november/what-is-different-about-latest-housing-boom-mortgage-debt-ratio/I was curious that house price/rent was used in the graph below, rather than housing affordability - to me, that has a lot to do with the sustainability of the market.

I'm semi-familiar with the city as far as socio-economic areas.

We use Reis and CoStar for the market data that goes into our packages, but its expensive not economical if you're just looking to keep up on the market.

http://www.ocregister.com/lansner/rent-687937-percent-reis.html“Axiometrics and Real Answers both reported that Orange County rent hikes averaged nearly 7 percent a year this past spring, boosted by rising employment and a continued economic recovery.Vacancy rates also remain low, ranging across the three surveys from 2.8 percent to 5.1 percent.Real estate agents reported seeing bidding wars among renters this year.

Beyond that, depending on the city, many lenders and economic agencies publish regular data as well as trade journals and apartment associations.