What steps should I take to move to Thailand, particularly regarding visa options?

If you plan stay here over 10 years. I would go non b company route and setup business here and going forward to permanent residency or even to citizenship. Retirement visa holders are tourists rest of their lifes.. You can benefit local social security etc rest of your life when you choose non b route👍

Alan, unless you are over 50, don't do it. It's too complicated to stay long term.

If you are at least 50 years of age and have a verifiable monthly income equivalent to a minimum of 65,000 baht, you may apply for a 90-day Non-Immigrant O visa on the basis of retirement. Upon arrival in Thailand, it is essential that you open a Thai bank account and deposit a minimum of 800,000 baht at the earliest opportunity. These funds must remain in your account for at least two months prior to submitting an application for your initial one-year extension of stay at the Immigration in Thailand.

This constitutes the first fundamental step; subsequent requirements may be addressed in due course.