Visa’s are new every year. You’ll have to reapply and provide required evidence. There’s no limit of times, can be 30 years but probably a limit of one wife at a time for visa qualification. 🙂
Might want to look at language schools as well. Yes you would need to do the Non O marriage to a Thai and you have the option to add a WP or a Non B which can affect your stay in Thailand as you lose the visa extension if you quit/get let go but the same would happen on a marriage visa if you quit or were let go by the wife.
unless you have an Elite visa or the LTR for wealthy individuals most other long term visas are 1 year at a time. As others have recommended it’s better to get acclimated and rent for a while (maybe forever). Not always but often when you have a property it’s difficult to sell.
It’s amazing how much easier and less worrisome life can be if you want to stay long term by getting an appropriate long term visa. Trying to get around the system will eventually put you in a precarious situation.