Some questions about my "City-issued Lawn Ornament".

So, i've had a stop sign in my lawn for a while now. I honestly hate it, as people like to throw trash in my yard. (Someone even smashed a beer bottle on my mailbox and i didn't see the glass till i stepped in it. Thankfully i wear thick-souled shoes.) But i mind it cause i have to.

Now, my grandpa owned this house when it was put in his lawn, he's recently no longer with us, so most of the responsibility has fallen on to me. He never got a chance to pass on all that he wanted to, so I have to ask…

What are the rules about it?

Do i have to fix it if it falls over?

If it's destroyed by some dingus, is it my problem? (Like it was when they ran over my first mailbox)

Can i put my garbage can by it? (My sidewalk ends right next to it.)

We have a small driveway, i know typical rules parking around stop signs, but does that change in a congested neighborhood?

What can i do about people throwing trash in my yard?

I dunno. I tend to overthink little things. I just don't want to get a ticket right in front of my house, or at all really.