The two main qualifications to have your LTR Visa to be approved quickly are the following:
1. Retirement income 80k USD or above... You will need a letter from your pension administrator to verify that this income will continue till you leave this earth.
2. Health care insurance...50k USD or more.
Myself and five other colleagues retired from the Honolulu Police Dept used these two criterias to qualify... Remember to apply directly to the BOI site... Good luck.
If you are under 50, apply for LTR visa, Thai Elite visa, ED visa, Business visa. If you are over 50, apply for retirement visa... Contact Thai centre on the Line app.