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I have them process credit card payments.

We normally do not seek judgement due to the expense that is involved, even after you win you have to continue to renew the judgement every year.We put them in collections and have it hit all three credit bureaus.

If Don fails to pay, the bank will certainly go after me, it will at least ruin my credit and will likely take me to court.

It sounds like the Title Co. was not aware that the tenant prepaid rent and just prorated the current rent for the month of closing, so agree if they had no knowledge of it, would not have ever gone on the settlement statement as a credit to the buyer and they likely will not do anything post closing to help obtain those funds. 

Perform the same task in each app to ensure a fair comparison.Load a property with pictures and details.Market that property.See what your marketing looks like from the public's perspective.Submit a fake application to see how easy the process is.Run a credit/screening report on yourself.Enter a maintenance request, assign a vendor, and attach a fake invoice.Enter charges to the tenant's ledger.Enter recurring charges and automatic late fees.Sign documents electronically.Run owner reports.After testing a few apps, one should clearly stand out.

I have already been fully qualified for both the line of credit and DSCR.

After all rape is just the word of the victim that it was not consensual sex, breaking and entering, well the door was already broken, every theft, every credit card fraud, well the owner said I could. 

Dedicate one checking account and credit card exclusively to real estate.

One tip: focus on areas with year-round demand and check local regulations early—they can make or break a deal.