there's more than one type of non o. Non o ( marriage) employment is not prohibited. In fact. I don't even tell immigration I have a wp. As I've been using the 400,000 in the bank method.
Brian. If you can follow a simple recipe, use a photo copier and are allowed to use a stapler unsupervised then have a bit of fun and do it yourself.
Michael Dawson posted a link to a very sad story above where a guy was thoroughly rinsed by an Agent last year and ended up on a year ( nearly) overstay. Lucky for him the IO in CW could see it for what it is but you could easily end up being blacklisted.
Agents are in no way regulated in Thailand.
Me and my cat Tommy could do a better job.
You can get some pretty good advice in this group and one or two other FB groups
Good luck. Keep us posted (almost nobody reports back. Take take take)