In stocks I prefer dividends.

However, selling it did not work to accomplishing my goal......which was: Build a real estate portfolio that would provide substantial, predictable,  and sustainable income that would allow me to live a very high standard of living for the rest of my life.  

No one can predict the market and what it will do.

A multi-year lease is extremely beneficial for both the tenant and landlord.The goal for the tenant is to establish a valuable home for a predictable period of time.

Very old housing stock?

So deciding which homes are "better" is something of a complex formula.So I recommend South Side and Friendship based on modern patterns of urban renewal along with some attributes of solid building stock that would offer value to an investor.

I agree that some tenants might like the idea of having predictable heating costs which makes it easier to do their budgeting.

However, I didn’t believe that would necessarily achieve my goals - especially considering that analysts don’t expect the stock market to perform as well in the future as it has historically.

Yes this is how you grow wealth, but it is for the experienced investor, and one that is not over leveraged and so can withstand a hit to the market (what if stocks crash next year, or current tax policy goes through reducing incentive for owner occupants). 

So when you know the highest is 6 you can stress test for years 6 to 10 and predict out cash flows somewhat.If you leave it open in year 6 to market that can be dangerous to do.I like floating rates or interest only rates more when a property is a value add and being turned around.