I just head up and tell the dock guys and I leave with 10 or so.Sometimes guests take them with them as they are pretty cool and I just have more sitting to put out.

This leaves $2600 after debt service (PITI).

Hopefully they will see you are not screwing around and will leave on their own.I hope you got a great deal on this property, because tenants in place are a liability, not an asset, in the Empire State.Now, who loves NY (besides our many "guests from out of town")?

Unit 3 - mid-term rental (this would be best for the most private unit as most mid-term renters are more concerned with privacy and creature comforts than amenities)4.

Property values have been appreciating rapidly in recent years, and the city’s population has started growing again—a trend we haven’t seen in decades.I’m also based in California and have been investing in Detroit for several years, so I understand the concerns of out-of-state investing.

I tried renting there one off-season, and I had the same concerns with guests overstaying. 

I could care less what happens to the prior homeowner or if they go after him, as far as I am concerned.  

Don't leave this option OFF the table. 

Would you recommend leaving this as is for 2020 taxes?

Any of these will leave you in a much better position for success, and provide a greater income while you learn.