Go to the immigration office you will be doing the extension at, and get a list of requirements, for instance some will require a TM30, some won't, Just do the extension when you have 7 days or less left on your current stamp, because some immigration offices won't allow you to do it earlier than that, the 30 days will be added onto your current stamp end date.
the Thais don't seem to look down on each other, for scamming farangs, so don't think he won't to save his reputation, a chanote is the Thai "land title deed" a usufruct agreement is probably best to lease the land, I think with a 30 year lease, papers can be drawn up for 30+30 but I've been told, it's only guaranteed for the first 30 years the second can be cancelled.
crop! any jpeg photos that are too big, they won't drag and drop, if you need to upload more than one photo for a particular requirement, do a collage.
check the size of the jpeg photo, if it is too big it won't drag and drop, just crop it, the other little tip I got from someone else, was it only allows you to upload one document, but on some it seems to require two or more documents, just do a collage.
Please note that you can send 50,000 THB or above per transfer only to the following banks from 7 January 2022 due to regulatory changes:
Bangkok Bank Public Company
Kasikorn Bank
Siam Commercial Bank
You can still send money to recipient accounts that use other banks, but you'll only be allowed to send them up to 49,999 THB per transfer. There's no limit on how many transfers you can create."