ROI Cashow analysis first mortgage Payment

[Rogelio Nunez]

Hello everyone, Question about calculating your ROI/Cashflow on property. When you close on a property, mortgage payments are in arrears so your first payment won't be due until next month. That first rental income you receive what do you calculate it against? For example Downpayment $40000 closing $10000. Other fees turning water on/appraisals etc$1000 $51000 opening cost. So obviously we calculate this against projected gross rent- minus debt service capex vac...and we receive our cash on cash return %. I have a situation were on closing a duplex on the Nov 3rd I recieved prorated rent, one of the tenants rent due on 20th and other 1st. By the time I payed first mortgage payment Jan 1st I received 4 rent payments plus prorated rent. Totaling $4600. How do I factor this? Against opening cost or divide into monthly cash flow? Best regards, Ro