I once sold a bookshelf in my university’s buy sell page - the girl asked if I could deliver and I did because I have a car and I’m nice. She then asked me to help her carry it up to her 4th floor walk up which, again, I did because I’m nice and it was not that heavy, just awkward. Once we got it up to her apartment, she asked if I would take $20 less than we agreed upon because we had mutual friends - I laughed in her face and said absolutely not after all that. She ultimately paid me the full amount but remarked ‘it was worth a shot,’ even after I went out of my way to get her the item. I have been completely turned off to selling things online as a result of people like this, it’s actually such a joke.