You take purchase price and subtract land value, which can be a lot in California.

Looking at the amount of work that was needed calculating the cost totaling up total cost and subtracting that from the ARV What was the outcome?

If you don't have financials, you can calculate the expected NOI by multiplying the number of occupied spaces currently paying rent by the monthly lot rent, then multiply by 12 months, subtract the expenses, which can range from 30-50% depending on variables, so use 40% for your back of the napkin analysis.

Even after subtracting mortgage interest, property taxes and insurance, I am still making a profit at the end of the year. 

If the terms were payment over X-yrs +/- down payment +/- interest you’d determine the monthly payment and then subtract that from market rent and that would be the payment she’d give you each month.

This is how you might be able to BRRR...Projected rental income: $172,800 ($200x12X12 + $144,000)- Expenses (if they were to remain at $72k) = $72,000NOI = $100,800Let's assume it appraises at a 6 cap, the ARV would be $1,680,000.Max LTV on new loan is 70% = $1,176,000 (assuming DSCR is in line)$1,176,000 - $700,000 (orig loan amt) = $476,000 but then subtract the rehab + loan fees for both loans.If you can fine tune the numbers with actuals and with some input from a property manager (as there are many variables here), we can clean this up but this is conceptually how I would look at it.Hope this helps!

Because you mentioned managers, I am assuming you didn't use a service like fundrise.But, you can't estimate profit without estimating what your estimated revenue will be and subtracting all the costs.I.e, how much longer does the roof have, what portion of the rent is being budgeted for future repairs, who covers the cost of repairs, how does the tenant request repairs, what are all the expected monthly expenses, how much is the management team charging you, how do you know the management team is doing their job, what are the names of the contracting companies they are using if they are constructing the property.

That means need to calculate what monthly rental numbers look like and subtract out the subject 2 payment, insurance, maintenance, vacancy, and YOUR cash flow.

If after 5 years you were to take advantage of 5 years of appreciation and sell the property, that roof would have only subtracted $1500 in total out of cash flow. 

If I subtract vacancy cost (4 x $3,200), the net rent reduces to $19,200/Yr, or a 4.8%.