@Brent Coombs frankly that credit can be as big or small as your appetite allows (it does cap at a certain point, and the credit cannot exceed the actual costs and prepaids). 

I would suggest coinless and app first, then credit/debit at the machine, then loyalty card system if you have a large apartment community.

Delayed financing will limit you to a maximum of the purchase price plus closing costs, and prepaids. 

The Express Carwash biz is once again a unique niche as it only requires 3 to five employees and is cash inserted into machine, credit or debit so employees don't have any personal contact with any cash.

A few thousand is taken out for closing costs (title, prepaids, origination fees, processing etc) and you walk with the remainder. 

Unknown if residential appraiser sees the comps the way you did when you purchased.Cost to refinance $3000 plus any points/ prepaid interest; does the loan you have when closed have a prepay penalty (many do).If you didn't qualify to buy how will you qualify to refi?

Different checkbooks, accounts, debit cards is just a bit much.You can separate expenses for each property by using QuickBooks or Excel spreadsheets, or whatever method you prefer. 

@Matthew AlbrittonHaving a separate bank account per property is overkill.Imagine having 20 properties and 20 different account number to remember, 20 different checkbooks, 20 different debit cards, etcJust have one bank account for all your rentals(assumed no entities are involved) and have a proper accounting software to keep track of the income/expenses by property.

The 2nd account would be for escrows, prepaid rent and be your trust/escrow account.  

12 accounts, 12 debit cards etc.