With a full gut like this, I’d rather overestimate than get caught off guard mid-project.

I'd underwrite the deal as any other - make sure you are conformable with the quality & tenant base. 

I'd talk to your broker on what it'll sell for after the fact and where the market is heading over the time you plan to own it. 

@Hunter Duplantis what @Gino Barbaro said is exactly what I was going to suggest.When you have vacancy is the time to experiment and apply your original thesis.I’m not trying to play Monday quarterback here but, you should be highly confident in where the rents should be well in advance of having a vacancy.That being said, after confirming competition rents on websites (I’d also recommend Craigslist and Facebook marketplace), you should be in alignment there.  

I'd try those 2 as well! 

I'd pivot the condo to a SFR in the Boston-area, but really analyze if your vacancy is prompting you to transact, then are you really fit to invest?

I imagine for people who have had accounts there for a little while would be approved quickly.Also on the cashout refi definitely hit up Community Bank.

I'd recommend this strategy for a new investor vs. doing a HML on your first deal. 

I imagine people who've had 2nd or 3rd houses in hollywood hills are not interested in rebuilding or doing the work. 

I'd echo what many of the individuals who have responded already have said.