It is purely "try this. cross your fingers and hope" strategy.

In my one rental that had concern about the possibility of asbestos tile (judged purely on the likely age of the tile) we just put new flooring over the top of it.

So, they are not getting as clean a wash with pure cold water.

If he is purely a lender, he will be paid via interest income and his tax breaks will come from his lending business, not the performance of the property.

Pure cash flow plays in flat or falling markets is one sure way to increase your risk and to lose the real opportunity of having your money work for you.

As I mentioned, I'm struggling to find guidance online for our particular situation since we own property, but it's purely a rental that we've never resided in.  

So, this is purely "HVAC 101".Where I live, the purpose of having them in the floor under the window is to keep the windows warm in the winter so they don't sweat/frost and the wood frames rot when the frost melts.

I could contract it out but I find great joy in doing the work.

Pure cash flow :)

Your tenants love their homes and don't want them to be sold from under them...that's it, pure and simple.