Hopefully, the tenant takes the hint after today’s conversation, but if not, you’ve got a solid plan.Question: What is the difference between eviction and notice of non-renewal?   

I'm confident a judge would see the picture evidence I have and go "damn!"

You are better off finding a solid property that needs light cosmetic work (paint, floors, or maybe even a kitchen or bathroom remodel), buy it at a decent discount and put 25% down or more (this is when you get best rate terms). 

If the note was just an IOU to evidence a debt, it wouldn't have value, thus, couldn't be sold.

I love how Airbnb just pay me based on the evidence without going through 6 months legal battle or 3 years of collection hunting. 

Without evidence, it's hard to say.First, you should educate all of your tenants to report excessive noise to the police.

After all, you have no evidence they agreed to pay rent or any of the other terms.

The sale evidently resulted in Quest’s owners getting zippo (hearsay, working to confirm that). 

In the end we presented evidence that no buyer would be able to finance it and got them to agree to 85% seller financing. 

Selling your duplex could be a solid move if it helps eliminate your revolving debt and gives you a financial reset.