If your time is worth $50 an hour, then pay yourself that $50 for mowing the lawn or fixing the sink, and subtract it from your ROI calculation.

The first floor has a full bathroom, and the lower level only has a half bathroom (toilet and sink).

NYC is too expensive for me at the moment, but my parents live in PA so it's a great option.I have $50,000 (give or take) in cash that I'd like to sink on a good property.

Do a few touch ups to the unit (curb appeal, patch drywalls, sinks etc).

A simple vanity and sink with faucets you could get for under $150 and PVC piping is cheap and easy to work with.

They do the complete installation onsite, they just shown up with the slabs and sink. 

I wouldn't sink a bunch of money into a new HVAC system then.

Leave a sink dripping, turn up the heat in the winter to 85, turn on the AC to 65 in the summer and leave the door open, do laundry every day, let their friends all dump old furniture for your trash service to pick up "free" (for them), and other ridiculousness.Utility rates will go up, and tenants will complain when you charge more.Most tenants don't see to realize the real cost of utilities and I wouldn't imagine would want a few hundred in utilities tacked on to rent.

There is a 50/50 chance the problems were tenant caused , like a clogged drain on a window a/c unit , people taking showers without closing the curtain ,  did someone overflow the tub of sink?    

New IKEA kitchen with granite counter tops, nice undermount sink etc ~$10k2.