Quote from @Christopher Robert Noland: Say I can get an owner finance on a 99k house for 5 years with a balloon payment. $2500 down. 

All you need is a single place to track tenant information, payment history, maintenance, and a few other things.

Digitize physical receipts for easy storage and use a consistent naming convention for easy sorting - 2024.03.25 Home Depot. 3.

Finally, there are digital nomads and some theater performers who need to stay for more than 30 days.

Deduct NEW property taxes after you buyDeduct home insurance costsDeduct maintenance percentage, typically 10%Deduct vacancy+tenant nonperformance percentage(we recommend 5% for Class A, 10% Class B, 20% Class C, good luck with Class D)Deduct whatever dollar/percentage of cashflow you wantNow, what you have left over is the amount for debt service.Enter it into a mortgage calculator, with current interest rate for an investment property, to determine your maximum mortgage amount.Divide the mortgage amount by either 75% or 80%, depending on the required down payment percentage - this is your tentative price to offer.If the property needs repairs, you'll want to deduct 110%-120% of the estimated repairs from this amount.Be sure to also research the ARV and make sure it's 10-20% higher than your tentative purchase price.As long as the ARV checks out, this is the purchase price to offer.It is probably significantly below the asking price.

Late payments do not bother me at all as long as they paid all their bills.

Write the property on the receipt and keep a digital copy and the hard copy.Quickbooks Online is a good software for both receipt capture and organizing what expense goes with which property.  

(Max vacated rents - your monthly mortgage payment) = +/- net cashflow.

Use less of that and either get the seller to buy down your interest rate or you can do it and have a comfortable mortgage payment and still plenty left for your emergency fund.

Also AirBNB stocking fees, maintenance, cap ex.But at the same token know that the principal portion of your mortgage payment is actually not a true expense so there is that benefit to doing all of this even if you are light on the cash flow or break even.