The refinance is going to leave us with about $20k left over, after the improvements.

They are not going to sit at a computer seven days and week and never leave the house having drones drop ship 20 packages a week to them.

Dont leave anything out on your lease, also as you gain more in years and experience your lease will continue  to grow and expand. 

I'm weary of rocking the boat and leaving my 3 investment properties to property managers.

There are feuds going on in every class of neighborhood over "Carl's leaves landing on my property".

We are about to get it under contract for 250K, they pay closing cost and leave all purchased material in the property(roughly 10K worth).

Since it's the holiday season, most of them are on holiday leave so it's a skeleton crew. 

Will you provide a porta potty, or not (think trips back and forth to the nearest convenience store or gas station, or worst-case, they use a corner in the backyard, which leaves the wrong impression on your neighbors)? 

She ended up leaving early because the neighbors were harassing her.

Never leave cash sitting in real estate doing nothing.