I would think they were worth a lot more especially with the current price of scrap steel.
Well here in Hampton Roads
we have what is known as the Ghost fleet. These are old large commercial
ships that have been given up rafted together on the James River. They are now moving away fast as scrap prices rise. I'm not so sure a 50 ft sail boat with a steel hull
is worth much just for the steel. They may command a slightly higher price new but as they age they lose value in terms of the hull
and gain in terms of the rust. Without regular maintenance
they rust exceptionally fast.
attached to the boat is worth more than the hull
is and it's age, wear, and condition matter more than the hull does on any boat. In a market heavily dominated by fiberglass boats it can be harder to sell them depending on the basic boat issues and the competition of other boats.
Boats are not a huge market like cars where there are many thousands of a single
model and color car with an almost unlimited number of buyers. It's more accurate to say the boat market is in all ways opposite that of cars. A larger 50 ft boat might on average take more than a year to sell.
The details of any boat will tell you more than what the hull is made out of. Most boats are priced close to what they are worth. There are not a lot of similar boats for sale
so it becomes hard to compare.