yes anyone can apply from anywhere. I was previously a resident in Thailand before applying for this visa with a work permit, but originally from Switzerland. I applied at the Thai Embassy in Vientiane.
Yes I heard it is one of the easiest from speaking to lawyers and other consultants. I have a balance of 500 k for the 6 months . I have both Thai and Swiss accounts. On my Thai account I didn’t have 500k for the 6 months, but I was able to prove this with my Swiss account (in French).
No, I just put my CV. It is a very quick process (no office, no interview), at least in my case. All you need to do is hand in your application at the counter window.