Discuss it with the company's HR department. I went back and forth between having a non-Imm B and a non-Imm OA when I was consulting for a Silicon Valley company that was outsourcing some of their manufacturing to Thailand. If your company has a good HR department and you have some value to that company, things like that can generally be worked out.
If there’s a multinational company that wants to hire you and they have a good HR department in Thailand they could probably get you the correct visa and work permit; if you’re trying to find a job with a Thai company with whom you have no prior relationship, then probably it’s a pipe dream.
structuring incoming transfers so that they are small enough to not be reported to anyone has the potential downside of making it harder to transfer your money out of Thailand if you ever need to do so. Generally you can only transfer out as much money as you transferred in.
maybe it has changed since I first got my retirement visa but when I applied what was required was a police report from either your current country of residence or from the country of your citizenship. A Thai police report wasn't required.
you don't need to be retired to get a "retirement" visa for Thailand, you just need to be 50 years old, meet the financial requirements, and not be working in Thailand.