Was recently approved for the LTR visa( Pensioner). Took approximately 2.5 months from application to approval. I elected to process the application myself , as fairly easy to do , albeit a lot of paper. I provided two years of bank statements to support passive income, outside of my pension income which was supported by income tax documents. Be aware though you require to have medical insurance (Thai) in place as part of the application and needs to cover up to at least 10 months while in Thailand.
I elected to go the LTR route as while presently hold the Elite visa, it expires next year and felt the amount required to renew wasn’t justified, or the “benefits” of the elite visa didn’t make sense for me.