Nothing to do with what i can afford. In fact your statement is a bit dumb as i would obviously have the money if i put in the bank. Putting a few grand in a bank is not an issue for me. Why pay somone to falsify something that may risk my ability to stay in the country when i can easily do myself and ensure that there are no comebacks.
I constantly see people on here talking as if 800,000 baht is a huge amount of money. It isn't really is it, if you are worried about the interest on that much probably best find somewhere else....
Having done all this through to citizenship when it was actually easier and i use the word easier lightly i have no idea how you think an agent can influence a foreign governement. If you are talking about them falsifying documents to do so i think they are pretty cute about that now and it will likely end up a permanent refusal...