@Stephen ******
We did ours on our own - it's really not that hard as long as you have the requirements met - $800 K Baht in a thai bank, rental lease, bank statements and letter from bank and it cost us only 1900 baht.
Eligibility:
Age: Be at least 50 years old on the day of application.
Financial Requirements:
Option 1: Hold a deposit of at least 800,000 Thai Baht (THB) in a Thai bank account for at least 2 months before applying.
Option 2: Have a monthly income (including pension) of at least 65,000 THB.
Option 3: A combination of bank deposit and yearly income totaling at least 800,000 THB.
Health Insurance: For applicants of the Non-Immigrant O-A (Long Stay) Visa, health insurance that meets the Thai government's criteria is required.
No Criminal Record: You must not have a criminal record in Thailand or your country of origin.
Not Prohibited from Entering Thailand: You must not be prohibited from entering Thailand under the Immigration Act.
No Prohibited Diseases: You must not have any of the diseases listed in the Ministerial Regulation No. 14 (B.E. 2535).
Not Engage in Gainful Employment: You are prohibited from engaging in any gainful employment in Thailand.