We budgeted for worst case scenario - as is wise to do with a foreclosure that has been unloved and unoccupied - and planned on replacing ALL of the plumbing.  2.5 years later, we've replaced just about all of it. 

I later get a call from her saying that it was alot of water coming from the laundry/HVAC room going into the kitchen and into the dining.

He then proceeded to make the problem go away.We continue to work profitably together quite a few years later.

Think of all the things that could go wrong and see if the lease addresses them: unauthorized pets or tenants, early termination, security deposit, lease violations, late rent, eviction, lawn maintenance, parking, etc.5.

It's a quick $1000 fix using our basement water proofing guys.We pump well away from the perimeter using lateral drains as many sump pumps just pushing water to the surface near the wall & it just heads straight down.

In all 3 scenarios, your ROI is almost infinite because you don't have any of your cash invested in the rental property AND you have between 20 and 25% equity in the property in case something happens to you financially later and you need to sell. 

When we signed the lease, I said that I would get someone down into the basement to add washer and dryer hookups ASAP to hookup the stackable washer and dryer I bought for the property.After having a plumber, an electrician, and an HVAC guy come down, I got those installed much later than I was hoping.

and if she chooses to give you some option or terms for purchase later that shouldn't complicate things with her 1031.Yep could work

Think of all the things that could go wrong and see if the lease addresses them: unauthorized pets or tenants, early termination, security deposit, lease violations, late rent, eviction, lawn maintenance, parking, etc.5.

Will need to increase rent later.