Positive Cash Flow Calculations

First calculate your projected monthly payment say 7% interest fixed for 30yr

Then figure out your project gross annual income subtract your annual expenses from that and you will get your NOI net operating income divided by 12 that would be your cashflow

I dont know that I've seen an actual formula, but assuming you know the home itself is a good deal, and dont anticipate any major improvements like roof, heating system, etc, its rent minus costs = your positive cash flow. Its just important that you subtract all your costs- any mtg pymt or hard money int payments, homeowners ins., mgmt costs if any, taxes, utilities if not paid for by tenant, and grounds mtnc - (lawn mowing-snow removal is usually owners resp for multi-unit bldgs). Also, to be on the safe side you should minus 3% from the monthly rent to compensate for vacancy hold costs inbetween tenants and put in a buffer for repairs/mtnc too if you want. Hope this helps you. Good luck!

thank you

Try this spread sheet. If you dont have actual expenses, rule of thumb is 50% of GSI = NOI

http://members.cox.net/hundredkhomes/MultiPlexCalc.xls

Great info here