Push credit and debit card payments hard, to make life easier for you (auto-payments), and make cash payments very difficult to do and/or not accepted (eg no office onsite, etc).

If I push them to get savings accounts/debit cards, are there ways to process rent with a debit card?

… @Lesley WhitleyThe new loan amount can be no more than the actual documented amount of the borrower's initial investment in purchasing the property plus the financing of closing costs, prepaid fees, and points on the new mortgage loan (subject to the maximum LTV, CLTV, and HCLTV ratios for the cash-out transaction based on the current appraised value).

They also prepaid six months rent!

I don't believe Ohio has any law regarding prepaid rent.However, if a tenant terminates a lease early, you are obligated to try and find a replacement tenant as quickly as possible and then release the first tenant from any remaining obligation.

Depending on the type of property, you will need 20-40% down payment, plus your closing costs and a few months of pre-paid interest (closing costs and pre-paid interest can be paid by the seller if you can negotiate that).

I does include prepaid property taxes and the 1st years insurance premiums.

I use debit cards.

I don't see anything in your post that would be a red flag for commercial.There are certain fees you cannot get a multiple discount on... for example, you will have to get an appraisal for each property, title fees will be per property, pre-paids (taxes and insurance), etc... you can't get any big discounts on these.. they are what they are. 

But, QBO gives a great financial picture as long as you manually enter prepaid expenses, depreciation, loan paydown, etc.