You may or may not wish to fix it since its likely too late to charge the last tenant's security deposit for it and also that it sounds so minor that people didn't even notice it right away.

We refunded his rent and deposit. 

From my point of view for event guest screening and security deposits, Superhog is reliable and integrates well for STRs and events, but you might need to adjust its setup for your use case.

Since you have 10k liquid, I would reach out to other investors in the area and see if they might need private lending for earnest money deposits until you are ready to buy your first property.

They manage specific funds on your behalf, and based on the time horizon, 3-5 years, they will deposit a payment back into your account on the 1st of each month, thus creating a monthly income payment. 

To lump in bitcoin as cause for that would be the same as lumping in the average bank customers cash deposit when certain banks launder money.

They weren’t thrilled about moving, but we worked with them—returned their deposit and offered cash for keys to help them transition into a new rental.

The security deposit should never be used for anything during the lease.

My friend recently told me of this scenario where the person I lease to would perhaps then double book individuals and keep deposits. 

He has paid rent weekly via auto-deposit into my account for 24 months.