The long term goal is to rent out to tenants long term and scale into multiple properties.

Appears to be a well oiled machine in terms of the construction and sale process-cookie cutter 1200 sq ft properties.

So, it won't be easy or simple and may not even be possible but worth asking about. 

Most work this way Rates: 9% to 13% (Most Deals are 11-12%)Terms: up to 36 Months (Most Deals are 6-12 months)Fees: 2-4 points(%) of loan amount paid at closing (Most Deals are 3 points(%))Minimum Loan Amount: $50,000 (For loans less than $250,000 $2,500 minimum fee)Max Loan: 65%-70% of After Repair Value(ARV)100% Rehab Financing Available (Require 20% of purchase price down payment or cross-collateral)Closing Timeframe: 48 Hours - 3 Weeks (Most Deals are 2 Weeks)NO PRIMARY RESIDENCES, NON-OWNER OCCUPIED ONLY, BUSINESS AND COMMERCIAL USE ONLY.

Factor in costs such as:Property taxesInsuranceMaintenance and repairsProperty management feesVacancy periodsLong-Term Strategy:With plans to acquire multiple properties, develop a clear long-term strategy.

From CSLB:This section defines what an owner-builder is and the laws surrounding the practice.An owner-builder is what the term indicates: a person owns the property and acts as their own general contractor on the job, and either does the work themselves or has employees (or subcontractors) working on the project.The work site must be their principal place of residence that they have occupied for 12 months prior to completion of the work.The homeowner cannot construct and then sell more than two structures during any three-year period.Getting a GC license and going Legit is pretty difficult.

In terms of doing a refi the house would be compared to others of the same value and adjustments made for BR or SQ FT. 

Nowhere is safe.  50 years from now short term rentals in residentially zoned areas will not exist. 

It will be difficult but not impossible to find a lender that will take second position and very likely the first lien holder will be apprehensive to a subordination agreement..The terms will not be as favorable likely in the 7-8%'s I/O but on a new mortgage there are investors that theoretically can finance 'unlimited' units..I think with our team it's 250+ up to $100M.

At least in terms of rent, college students are paying 1100 - 1600 to rent by the room.