So here is my situation, I have two 2 rail Atlas O Bangor & Aroostook GP-9's that I need repainted and relettered for the Nashville Chattanooga & St. Louis. I've already stripped the engines of their radiators on top to make them appear to look more like GP-7's, because the NC&StL only had GP-7's. I also relocated the horns to the proper locations to match the NC&StL's prototype, as well as added the proper headlights.
So now I just require a skilled painter to repaint and decal these engines. It's a relatively easy job, just stripping the paint, spraying the trucks and fuel tank black as well as the hand rails, and the body maroon. I already have the decals for the yellow stripes and the lettering. I just have zero expertise when it comes to repainting and lettering a locomotive.
Hi Ben, I would do a "search" for custom painting in the forum search. This subjects has been brought up many times and you can find all the past answers and people to contact there. It is always a good idea to do a forum search first if you are seeking particular subject help.
If you still want to get someone else to do it, do what Tex (Steve) said and do a search on the forum, there's a few well-known painters who can do what you want.
Here's a Williams E7 I stripped and repainted for Seaboard Air Line:
A modified MTH CA-1 caboose:
A Weaver PS2 2-Bay Covered Hopper:
A MTH 0-6-0:
I'm by no means a great painter, but if you take your time you can turn out a few nice pieces at a fraction of the cost.
If you do decide to ever get a compressor and airbrush, get a compressor that is quiet. Mine makes a racket and I find the noise alone makes me get in a rush. I had the Iwata girl at the IPMS show in Va. Beach a few years back give me a demonstration and I couldn't even hear their compressor, which was less than 5 feet away.
Actually, the best and most highly sought is Jeff Sohn. Not sure if he is still in the business, but many, many OGR folks have used him and always with rave reviews. His work product has appeared on this site many times and he is fair.
One thing to bear in mind - custom anything takes time. First take a wild guess as to how long this might take - four hours? Multiply that by your hourly wage or equivalent, and add a fudge factor because the painter gets to pay his own FICA, health insurance, and equipment costs, and you will see why most of us learn how to do it ourselves.