. $20k in reno to add another room is a pretty bad ROI - I'd rather take on a full rehab with a higher ROI, likely.

@Dominique Rogers finding deals is the trickiest part.. that is what I do full-time.

Ideally you can extract your initial purchase costs and the cost of the rehab but in full disclosure I have never been able to get all of my investment money out via this process (but I have gotten out almost all of my investment money).I am a big proponent of the steps I outlined. 

They ended up complaining about everything and only paid the first month's rent in full.

Should the tenant pay the full amount?

It looks like a few times they've paid a big chunk to get the balance back to zero.Also I think if I were to put about $10k into it I could get it rented for around $1100.If I keep the tenant there's around $1,500 in repairs that I would probably do but not all of it is absolutely necessary right now.So I know getting a long term tenant is usually something you hope for but if they seem to be struggling to pay rent on time and in full is it worth it?

Sure, a smaller one that would be less expensive to run for just HW, but you won't see a full $40k/year reduction in your utility costs.On the plus side, having A/C will probably be a differentiation point for your complex.

We also couldn't quickly turn the rental because we had to wait for repairs so we were also out a full month of rent since we had to cover that ourselves (and not included in the total $18k)It it were less, I would write it off as part of doing business as a landlord but $18k. 

When I was full time in Memphis I found multiple deals literally every day and flipped them mostly to other wholesalers until I had my own buyers. 

Anything else besides a briefcase full of money?