I was initially thinking one of the light gray vinyl plank choices, but wondering if that would clash with the existing flooring at the transition (by the breakfast bar in the photos) Any advice would be appreciated!

Considering that they should be out and are basically pulling a fast one on you (POA's should be negotiated during the initial contract signing, not after closing), I would charge the very upper end of market rent and demand a large security deposit.

@Cody Lewis @Coty Dolan Not to derail from Coty's initial question...but I would be curious to understand any instruments to use when receiving private funds from a lender?

@Mario Casarez sorry I am just now seeing this post but you mentioned something that is really important in your initial post - you want to use the HELOC for the down payment? 

A "Full" BRRRR is usually referred to when the entire initial cash investment is pulled out at the refinance stage.

Please dont set up anything before talking to the professionals as you might throw down the cost of the initial set up.  

Typically the hard money element in an initial BRRRR is to cover a cash shortfall between your own cash on hand and the cash position a mortgage lender requires. 

The math doesn't work for long-term rentals though for the same property.After initial research, my search was severely limited by city zoning prohibiting short-term rentals in many oceanfront areas but there are still some options left.I'm looking for opinions of skilled investors here about short-term rentals with Airbnb/VRBO.

If you do decide to take that risk, a good way to keep costs low initially is to consider new(er) construction.

The initial plan was to renovate as vacancies became available.