Also, what website would I use to target absentees, evictions, foreclosures, etc. to gather my list to send direct mailers to them?

I know easier said than done.On the flip side, you should be able to get an amazing deal on the property since it's empty. 

There are more details but I tried to summarize to make it an easier read.

@Harrison CookYour post kindles lots of questions.In the "good old-days" most heating systems were vastly oversized for the building they were heating - energy was relatively cheap, insulation was non-existant to poor ... so it was easier and safer to {drastically} oversize.Today, while energy {in North America}  is still relatively cheap for the moment,  we have a much better understanding of how to make buildings more efficient {though you might not think so looking at the construction industry in the U.S.A. and Canada}  and there are often more cost-effective measures than simply replacing an old, over-sized heating plant with a new, over-sized heating plant.You really need to - or at lease should -  perform a heat load analysis to properly size your heating system, a component of which, is determining the rate of heat loss of the building envelope.  

@Brian Schmelzlen Getting a seasoned apartment is easier said than done.

I paid off the mortgage on my properties and decided it was time to hire a property management company and take life a bit easier. 

That’s often easier said then done but that’s gonna be your best bet.

It's a lot easier to retire at 40 if you believe you can have the quality of life you desire with $20,000 a year.

You can also buy targeted lists from them at a really reasonable rate.

I would like to have a portfolio of rentals netting >$200k annually and then I can rest easier.