The tax rate would be 20%?

Live in one unit - It's a great strategy when using a bank for financing as the down payment and interest rates are more favorable to owner occupants.  

It seems duplexes are valued on rent rates for the most part.

., $300 for paint and supplies) and add a fair hourly rate for labor.

I would suspect once investors digest the higher rate environment and some of the hurricane damage is moved inventory will settle out in neutral territory. 

They have a group of funding sources that will compete against each other, this helps keep the final interest rate within reason, and offer a partial refund if they are unable to secure financing. 

If the market is tough, I reduce the rent rate over the full 12-month term.

Nightly rates and estimated revenue based on all the other units in the area?

An interest rate that works for her. 

Where in a standard market rate rental a stain like that could be handled when you get around to it and the rent would still be due.