Pulling permits, hiring licensed contractors, being someone anal about the carpenters/cabinet installer/tiler/painters work.  

When it comes to refinance, you either will have to secure the appropriate zoning or obtain a special use permit to comply with local ordinances.

Of course, there are a lot of things to look out for...setting up an appropriate contingency reserve for unexpecteds, getting an accurate scope of work, properly knowing what your time-value-of-money costs are going to be, making sure you're contractor is not pulling crews for other customers, knowing codes and getting your permitting right, and the list goes on.

I am interested in establishing a Short-Term Rental (STR) in Oceanside and noticed on the City website that STRs are permitted only in the Coastal area.

And if you have multiple series inside the LLC you will not be permitted to use the name of the LLC on subsequent applications for additional series.

Duplex have different zoning that may permit additional units.

Each contained historic use permits and have continually operated as 3- family buildings.  

@Ka Vangyes, you can use a HELOC for a down payment as long as your debt to income ratio permits getting a loan for the balance.however, i strongly, strongly recommend against it. 

The only place they WILL NOT JV is in my home city of Philly... go figure. something about taking too long for permits and inspections.

The costs of land  , engineering , site work , permits , labor , and building materials make this virtually impossible . then there are zoning issues and the rest of the politics that go along with this .