Best to have 20k Baht like others mentioned. It’s not a lot of money but if you’re asked and don’t have it or an equivalent currency you can be denied entry.
Tod,my wife has her own homes as do all of my in laws. They wouldn't want to live with me should that occur. No,I didn't supply the monies even for the current ones. Some Thais are very successful.
The Usufruct was my wife's and families and their attorneys idea to protect my interests. I had not heard of one before it was suggested to me.