For reference:-
The Thai jet ski scam is actually quite a simple one. A foreigner rents a jet ski in Pattaya or Phuket for an hour or two and goes off to have fun. When he returns the jet ski, the owner tells him it now has damage on it that it didn’t have before he rented it, and will often even produce photographs to prove it.............the photographs have been photoshopped while the poor unsuspecting tourist is off having fun on his jet ski but now the Thai owner wants 40,000 baht ($1,300) to pay for the cost of the damage.........this is often done in an intimidating manner and with a group of Thai men hanging around looking threatening................ simply pay up just to avoid being harassed or threatened........................
https://tastythailand.com/do-not-rent-jet-skis-in-thailand-its-famous-for-jet-ski-scams/#:~:text=The Thai jet ski scam,produce photographs to prove it.