This causes them to be walking a tight line following the minimum requirements for the short-term rental loophole.

The contractor is supposed to know what requires a permit and what doesn't.Now you know. 

We have good friends who are taking this approach  and we understand all the requirements we need to meet, which we are confident she will be able to do. 

Invested in basic index funds and paid down my mortgage faster than required (11 years off the mortgage by year 6).

I would add, also check to see if you state has court cases on line.

It is better to offer a discount than to just require it.

Shop Around: Compare rates from other commercial banks, credit unions, or online lenders to find competitive offers.5.

I'd think even where sub to or seller financing is most common, maybe the markets where it happens the most, maybe it achieves 2 or 3% max.The few times I see it in our area personally, is almost always on a 5-10 unit non-performing asset that someone can't get a loan on because of the debt coverage requirements.  

I'd start out by looking for contractors that have working knowledge in the remodel business as they will know the scopes required to complete the project.

The best way to protect yourself investing in NYC is to buy higher quality assets and require exceptional credit credentials from your applicants to obtain approval to rent.