Most of my tenants have been great, but once in a while I get people who can't figure out which shoe goes on which foot without help...

I was in your shoes once, and ended up helping my friend manage her 4 bedroom house that we were living in as roommates after she moved to out.

I know this may pop a red flag for the buyer but how much would that affect you if you were in his shoes?

Now that you know your tenant is affecting the quality of life of the next door neighbor, which is a public nuisance if I remember the law class correctly, and you have a duty to take care of it.But, this is what I'd do in your shoes, to try and keep your neighbor from suing you.  

While every market is different, it’s important to put yourself in the guests shoes to cut off pain points while also keeping your objectives in mind.

It's more of a showcase store.

You wouldn't be required to report anything, but if I was in your shoes, I'd report it.  

Looking back, I think a few things I did right (at first by lucky accident, and later by deliberate planning) made this possible:1)I timed my appreciation plays very well ... not that I nailed the absolute bottom of the market upon purchase (though I have), but like horse-shoes, hand grenades, and nuclear warfare, close is sometimes good enough.

Open up the floor registers and clean them out, this is not only good for your HVAC system, but also will reveal things like cigarette butts (unauthorized smoking), pet food (unauthorized pets), and the occasional kid toy (this is okay, since finding a barbie shoe or the missing lego will make a child happy.) 3.

I would eat the bill if I were in your shoes, thank the tenant for informing them of the issue.