Just to be candid and realistic - we are not in a cash flow environment right now. 

Quote from @Jeffrey Hill: There are a couple of challenges with financing the difference. 1) The current servicer has to approve it. 2) Finding a lender to do a 2nd mortgage at 100% CLTV is almost impossible.

Challenges?

Vet potential partners carefully and aim for relationships that can grow with your portfolio.In this higher interest rate environment, focus on cash flow and creative financing options like the HomeStyle rehab loan or seller financing.

Risk that the IRS will challenge it, which is far more likely than with a full-service professional report3.

Challenges include depreciation in market value (i.e., mobile homes often lose value over time unless they are situated on owned land) and tenant turnover.However, tax advantages include depreciation deductions, which allow you to offset rental income by writing off the property's value over time, and cost segregation, which accelerates certain deductions.

We are seeking joint venture opportunities with experienced developers who can see the value in this project and help us navigate these challenging times.As partners based in NYC, this venture was beyond our usual real estate development experience.

I think BRRRR would be quite challenging as a first deal in an out of state market, but that is just my opinion.

Quantifying it is more challenging. 

Challenges?