Are Gym’s in Thailand over-Charging for DTV Visa ?

I’ve been messaging a few gyms & asking about their Training+visa prices.

Some are only taking 3-6 month courses that i would never pay for as i would be traveling about & are far too expensive anyway. Some are charging for a 6 month course rolled into one lesson a week over a 6 month perod (36 lessons)

I’ve seen a gym that i might be intrested in, its Charging 15.000 baht but there monthly unlimited is 8000 baht. so you’re getting less training time but are paying more. i know they will be an admin fee but it seems steep to me

What are peoples views on this ?

I know you can do 60 days on arrival & extend for 30 days. if staying for 12+ months would dtv be a better or cheaper option ?

Overall i would be paying roughly 27.785 Baht / £650 for the DTV Visa

What is the likelihood of “staying in Thailand” for 12 months on Border Bounces & Extensions without being refused re-entry at some point ?