You need to know how much it will cost to build a house on each lot, and then subtract that cost, plus your fixed costs and your desired profit, from the ARV. 

THEN subtract out the mortgage and see what if any you have left.  

Calculate the NOI by subtracting all operating expenses from income.  

Being a renter previously, I’m saving an additional $1250 every month by not having to pay rent/mortgage, so I was actually subtracting the money for repairs from there. 

If you know the gross rent roll, subtract NOI and see if the expenses seem legitimate.

You need to estimate what all the repairs will cost, double that and subtract from FMV if the building were in good shape.

They are for the lazy and for those that can't add and subtract more than 3 numbers at a time. 

For mobile homes older than 1980 please subtract $100 per month.Thank you Al for watching over our real estate community and alerting the authorities should you find any infractions.All the best,John Fedro

Subtracting the expenses, vacancy, and debt service from the $3600 rent leaves $457/month in cash flow.The stated expenses plus vacancy are only 32% of gross scheduled rents.

I was referred by a fellow Investor.I met up with an Attorney and I got the feeling that they do indeed understand Real Estate from the investors point of view.They do double closings, assignments, etc.only drawback is cost: They require an Upfront retainer of $1,000 and subtract your legal fees from that.The double close transaction fees they quoted me were high too.