Neighbors throwing garbage on my property

[Jared Rolph]

I need help so me and my dad have this 4 plex and we are trying to fix it up, but some one that lives near it threw a sofa a really heavy one on our property we know we're it came from should we throw it back or what we don't want to cause trouble but we don't want to put more garbage in are yard, just to let you know this area isn't the greatest area, what should we do?????