Hooked, you got messed over, and unfortunately there are those folks out there. It is not just Clist though. I had a guy on a 175K house do it too me. Seller made the time for the appointment to re-look at it (ripped pool that was covered) and the agent called me the night before and said they had already sold it, after counter offering too us........ Yep, I was mad, but it worked out better actually. Could have sued, but it would be pointless.
When I sell on Clist, like my boat, I am just as upfront as I can be. Lots of calls, tell them first come first served, folks that were coming from a distance I set a time (in the near future) where they could be there and I would hold till then, then following calls I told them they should check back with me after that time.
The couple that bought it, came and looked, wanted to go look at some other's, I told them no problem, but if the next guy coming in the drive wanted it (and there literally was) that it was his so to call back before coming out.
I think as it goes back to the bible, just treat others as you wish to be treated and it all works out fine.
Hope you find the MH that works for you, I bet you will.