How can I apply for a Thai retirement visa using the 65,000 baht per month income without an agent?

This post seeks personal experiences from expats who have applied for the Thai retirement visa via the 65,000 baht monthly income route without using an agent. Users share various experiences and necessary documents, such as bank statements, letters verifying income, and other requirements needed for a successful application. Discussions include the initial income qualification, how the process varies by location, and the importance of specific paperwork when dealing with Thai immigration.