Keep in mind that mine is just an opinion but $15,000 is high and sounds to me like they want to recoup paint and vinyl top costs. They have not done anything else it appears.
Remember the comment earlier about some "rot". Make sure you check out HOW that was repaired.
There is very little difference between a very nice 49 Kaiser and a 49 Virginian in terms of market density. There are very very few KF guys ADDING to or adjusting their collections. Most are getting out and wanting way too much for their cars to supplement their retirements.
The rest of the collector world does not really care about Virginians. These are cars where you have to start the narrative attached to the auction by explaining WHAT it is. You don't have to do that with muscle cars or Corvettes, etc.
The market is small and shrining for late 40's cars in general. Don't worry about selling it to KF collectors - none will be interested when you go to sell. It would have to appeal to someone on ebay. That's about your only marketplace that puts national eyeballs in front of cars. Then you "might" get lucky.
If I were buying this Virginian, I would want to know what they paid for the car, or find out, then I want to see the receipts for the paint. I am not paying them one cent more for "profit." That said, I obviously would not go $15,000.
There was a stunning, correct, low mileage Caribbean Coral Virginian for sale in Georgia for 3 years and I want to say it was $18,000. It ended up selling for $12,500. It was correct, great popping colors (I like this color) and turn key, southern no rust car.
There is no market demand for these cars. That's different from saying people will look at the car and be curious but that wallet grabbing must have demand is not there.
I'd go $12,000 tops subject to viewing receipts and adding up. If you want to bail them out so they break even then it may be a win, as I often advocate for improving the gene pool and these folks have done it. But to use an incorrect top material and stop at paint and top - means they are tapped out and know that anything more they put into it will be like dumping money down the drain.
Proceed with caution.