There used to be a internet site called Tall Ship Models inc. that was owned by Morey Benton in Canada, which went defunct a few years ago. You could post picture of your built model on his site and once it sold, you paid him a commission of 15% if memory serves. I received commission work from his site as well like building a USS Constituion for an Insurance Corp. in CT. Another USS Constitution for a Internet Software comp. in New Jersey. But the trick is, you have to Package and ship them, which I quickly got very good at. Back then shipping was not nearly as costly as it is today. I could pack and ship a model through UPS, FEDEX from $50.00-$75.00, but now it would cost three times that price. The last R/C boat model I shipped last year cost $150.00 that doesn't include packing materials.
Now The rule of thumb for pricing a built model back in the 90's was 20 times the cost of the kit, but now a days with kit prices 4-5 times the cost that they were back them is not justified. To give you an idea of what I usually get for a finished model breaks down to about $1.00 an hour for my time.But this is only if it's a build that I chose to do. Now if it's a commission build, my fee is around $5.00 an hour for my time. So if I built a Cauldercraft HMS Victory, which can easily take 1500 hours, my price would be $7500.00 plus the cost of the kit and additional supplies, so the total could reach $10,000.00. Don't be fooled by those ship models you see on ebay for a few hundred dollars and free shipping, they aren't the same quality by far.