Is a Multiple Entry Tourist Visa the best option for a 6-month stay in Thailand with trips to neighboring countries?

I’m from the US, and I really want to visit Thailand for 6 months. Do some trips to Cambodia, Vietnam and possibly Myanmar , but choosing Thailand as a home base for the majority of those 6 months.

Was thinking getting a Multiple Entry Tourist visa would be the best route but thought I’d ask if that’s what you all would recommend? Or if there’s a better option I should look into.

Thanks so much!