Their verbal quote is $230/sqft including all material. 

The best way to get leads in this digital age is through PPC advertising. 

Hire a local full-service property manager to handle the property maintenance, the housekeeping, the inquires, bookings, contacts from guests & advertisements.

I’m a video editor by day - working primarily in advertising & marketing, with some dabbling in TV promos and movie trailers.

I Do not know of the legalities, but when renting in this area I have seen people advertising renting out a camper in their yard once and renting "apartments" above garages many times which would be similar to an ADU.

This makes a big difference as if you get contractor's on a house by house basis, it's probably 10-20% markup in labor and material costs. 

As such, it may make sense to sell (David Greene has a lot of material on return on equity, so I suggest reading up on that before making a decision).

I love finding great reading material (for ANY subject, really).

I’m trying to find out some help in to how I can get a loan for the property and for the Materials

The investors I talk to are running at about $10k in advertising for 1 deal.