The only person who is not suspect in this case Is the person who called the victim to ask about the horse ahead of time. The victim told the looters he was the rightful owner, and this was a hoax, and to leave his stuff alone. The looters ignored him. I would say the truck that sped off with the victims ladders, lawn mowers, etc was clearly "intent to pernanently deprive."
Everyone else is suspect and could be a clever thief, whether or not they return the property they took. I doubt they left the victim an itemized list of the property they took and where to contact them....
And anyone one that waves a printout of a craigslist ad as proof they can take whatever they want is stoopid!