Rates are very comparable to conventional. 

In investigating the out of state markets I determined that the more inexpensive options were just not properties I would want to own because they were in too bad a condition and renovation costs would make them comparable in price to what I can get locally.

I am looking to understand the ROI on the investment under the two scenarios and how to correctly estimate the differences in total return between the two options, assuming the positive cash flow ($28K/year w 3% growth rate) is reinvested and compared to keeping the $260K in the stock market.

Can anyone here suggest how I can get comparable information on the last stage of the process?

You can use sites like Bankrate and NerdWallet to quickly compare banks and see who is offering the best return on your money. 

My only plan when I started this was to earn a better return than anywhere else by using my comparative advantages (high knowledge of construction, DIY abilities, intimate knowledge of my geography, location in a cheap but growing area) to affect my return in a way that was impossible in other arenas.

Local brokers in your market will know the current cap rates for the property class, mainly based on recent comparable sales.

So I'm doing some comparables on what sold in the last 3 years in an area we're actually looking to do a new construction.

When prices compared to rent were more affordable, I thought the 50% rule was conservative in San Diego but I no longer believe this to be the case. 50% rule is fairly close easy predictor. 

I need to research all 4 and compare fees, interest rates, and tax benefits.