And fwiw, I live here and own a vehicle and have only entry stamps. Two years. I had a tourist visa for my first entry. I should add that I always travel by air and exit, at times for several weeks, though nothing has ever been said to me by anyone in immigration, even when I do return after just a few days.
Go to sky scanner.com and type in "from" Chang Mai and in the "to" section type "anywhere". Put in your dates and search. It will give you the cheapest flights for destinations out of Chiang Mai. Yes, you can come right back.