What is the best visa option for a 24-year-old looking to move to Thailand for 6 months to a year?

Elite five year

The best thing that I wished I would have done is get the multi entry visa. It would give you up to 9 months. I would time it where I wouldn't have to stay here for rainy season lol. Just fly in and out 3 times. Visit other neighboring countries for a couple of days.

Best and easiest way is to apply for Multi Entry Tourist Visa in your home country. It will give you a max stay of 9 months. But you will have to exit and renter every 90 days.

1ลานบาทพอแล้ว

6 month to a year? Without leaving the country this can only be done on a Non-Immigrant visa. There is several categories of those. The most likely that could apply to you is the ED (Education) category. Meaning you would have to sign up for e.g. a Thai language school or something similar.

If you don't mind leaving the country in between, you could also check the tourist visa route. TR Single Entry would give you 60 days and can be extended within Thailand for another 30 days. So roughly 3 months. You would then have to leave the country (e.g. to a neighboring country) and start over with a new / fresh tourist visa. Alternatively, you could also get a METV (Multi Entry Tourist Visa), with which you could enter Thailand unlimited times during a six months validity period and stay 60 days (+ potential 30 days in country extension) each. With the latter you would still have to leave Thailand at some point, but would not have to bother with needing to obtain a new Singe Entry TR.

Cheers.