Our deal volume and inquiries from the Columbus area have seen a large increase over the past year so we are familiar with the market.

Last time I did that, my costs came in right at $1000.The OP is vague because it does not address size or location of heater, type of fuel, self-install or hired, permits required or not, and whether or not they care about a specific brand.  

We need that experience as landlords before we can do any other investments and to be confident in doing so.

I suspect most states have a similar process otherwise landlords would try to use any absence by a difficult tenant to execute a self help eviction in this way.

I think the best way to overcome analysis paralysis is to align yourself with an agent you like and trust and who is well-connected so you feel confident you'll have the support you need to close the deal and get off to a good start. 

My thoughts are 1) I will have a fixed rate and not worry about it changing every 5 years thus helping me control my expenses a little better (of course aiming to secure a good rate whenever the rates hopefully come down), and 2) it will be amortized over 30 years and if I get a good rate, then my cash flow should increase by a decent amount. 

Fire them, they failed at one of the most important parts of PM - collecting rent.Be very careful about taking steps to get them out, in Virginia if you do something like try to force them out you can be guilty of "self help eviction" which will cause the sheriff to halt their work and will get you into legal trouble.Cash for keys has worked for me in the past but it isn't guaranteed.

Not sure how long you have been around, but when markets soften, these types of assets get crushed because vacancy rates increase which causes condo fees to increase due to the amount of delinquency on the books.

Mistakes in a Solo 401k (have to be self employed and no w2 employees other than spouse) can usually be fixed.  

However, we have to submit evidence for the voucher increase to happen.