Take lots of photos with geo tag location and date so its put back the same. Let them do it for a fee. Im sure you'd be charged if it was the other way round.
I would draw up a contract for this as you may end up with problems down the line.
Maybe stating who digs up the road if theres a water leak etc.
Its people who overstay make it difficult for us genuine people who stay here.
Get it organised. Its not difficult to go to immigration and pay 1,900THB. If you have enough money to stay here on overstay then you must have enough to stay here legally.