I would like to suggest the addition of the OPTION to sell ships for Turns OR Gold Coins.
Currently when you sell ships to the shipwright you can get back 70% of the Gold Coin value of the ship. I would like to suggest the seller have the option to sell ships for 70% of the cost of turns to build the ship as well (rounded)
Howker - 8 Turns to Build. 8 x 70% = 5.6. 6 turns returned.
Merchantmen - 22 Turns to Build. 22 x 70% = 15.4 15 turns returned
Frigate - 80 Turns to Build. 80 x 70% = 56. 56 turns returned
Turns cap of 600 still applies. If seller attempts to sell above 600, standard full of turns message would appear.