It seems that the #1 issue for the sellers is not recognizing taxable income and the #2 issue is that they don't want to actively manage their next investment, yes? 

They have the experience and expertise to build a robust online store, optimize its conversion rate and handle the technical issues involved in creating a successful eCommerce platform.

I thought about delaying the move in date until the security deposit was in hand but then realized if they have issues with the deposit they would likely have issues with rent.

This can also cause issues with both title insurance and homeowner’s/landlord insurance. 

Its an inconvenience to make your tenants "not only" have to pay a monthly fee for a P.O.Box, but run into so many issues not having this will cause your tenants.

It's a turn key, good flip with a few minor issues. 

There are also title issues that go beyond liens.

@Mauricio SandovalI was getting extremely high insurance quotes for our properties in Ohio, then I realized after reading forums on BP that you have to ask them to quote you on Actual Cash Value, not rebuild cost (which are extremely inflated during these times of supply issues).

I would then follow up with the upstairs tenant and let them know that I had issued the offending tenant a written warning about the behavior.

Most places should rent, but the issue comes down to marketing and pricing the midterm rental.