The "normal" visa extension is 1900THB a year, so your paying dearly for it, but if your under 50, not married to a Thai and don't plan to make an heavy investment here, it could be worthwhile. There are benefits with the Elite you should check out.
Jamie Watt BOI needs investment, like an office, workers and cash, I donβt think you can run it from your home country. But you need to find out more.