Hey there Dennis... welcome back to the thread and welcome back to Thailand!
That gas money is a given, if where they want to stay is better than where they should go back to.
A high wall, solid gates, CCTV entry and a crocodile inside are all essential.
So.. those stair posts? They have been treated for termite control, but of course, anything out in the elements will eventually suffer, so there will surely be upkeep,
But I will be jobless with time on my hands (you can't lounge around in the pool with a beer all day every day) so i can do it!
Seriously, yes...houses need maintenance same as anything. we will just have to make a plan for that and other areas too.
Just remind me cos i am getting old n i think Alzheimer's is setting in, where are you based in Thailand?