There's 3 guys here on the Forum that custom paint engines & they are quite good at it. They also have an excellent track record(pun intended) & are not cheap. They have been painting engines, installing electronics, DCC boards. super detailing, etc.
So, like someone just said here on the forum, pictures speak a thousand words or a thousand pictures. I also paint my own w/a rattle can because I can't afford a custom painter. You have to figure shipping costs both ways, paint, time, sand blasting or stripping the engines for paint & detailing. It's not just the painting that is involved.
Just my 10 cents worth.(the economy is going up, so, 2cents isn't enough anymore).