What rule was applied in this pre-foreclosure deal? Was it the 70% rule?

ARV: 419K

PAY OFF STATEMENT: 259K

BACK PAYMENTS: 10K

REPAIRS: 20K

MONTHLY PAYMENTS: 1600

SELLING TIME: 3 MONTHS

TOTAL MONTHLY PAYMENTS FOR THE SELLING TIME: 4800

HOLDING COSTS IN THE SELLING TIME PERIOD: 3000

CLOSING COSTS/ATTORNEY FEES: 8000

INVESTOR'S PROFIT 15% OF THE ARV: 62K

TOTAL EXPENSES: 368K

368 (ARV) - 368K (TOTAL EXPENSES) = 50K - 20K (MY FEE) = 30 LEFT OVER

Left over can be used for unexpected repairs,realtor fees, etc etc