I read this thread before going to bad, then had bad dreams about the fates of little duckies paddling their feet as they got taken away in sacks to uncertain fates. My ducks get spooked over a new food dish so I can't imagine their terror.
Good luck and don't be afraid to go with your gut. You will sleep much better. There are people who prey upon others and are practiced at it. You do not owe them anything. Be strong.
You never know what sort of oddball things can happen or people will appear when you post something for sale. I posted some sheep for sale last week on CL. I got a few legitimate responses, but also got emails that responded with my exact subject in their text: Do you still have your beautiful jacob sheep (location) for sale? Half asleep, I responded that I did, then got a pre-fab paragraph that I wasn't selling my stuff for enough money and to follow such and such a link to find out how to get more. So it was at least obvious phishing, if not trying to unleash who knows what virus if I opened the link. I'm not especially savvy, nor am I paranoid, but you really have to be alert to these possibilities.
As far as the actual humans who do respond, there are a range of idiots. Although I explicitly stated I wasn't selling the sheep for slaughter, people still asked about them for meat. For those who seemed genuinely interested in having the sheep as pets/lawnmowers, I tried to be fair in my responses, and even make everyone happy by not selling them all to one person. Of course this could leave you in the lurch.
It's not just buyers who can be clueless or unscrupulous. A lot of sellers seem to try to get as many buyers lined up as possible, then when you go to get your item, tough luck it's gone. I responded to an ad about a picket fence that required that I remove it from the ground and haul it. After I few days, I got an email saying it was still available (gotta be super quick on some of these things!) I figured their first offer fell through thus the delay. I said I'd give them exactly what they asked and I was completely flexible with time to come at their convenience. I began making arrangements for getting the fence out and hauling it. When all my arrangements were set, I emailed yet again asking what time was good for them. Three days later they emailed back that the fence was already sold, even though I thought it was offered to me and always got back to them IMMEDIATELY