Build quality is critical. If it was carefully fitted with good internals and everything is in spec, it will be worth quite a bit. If not, then it's worth less. So long as the main components aren't trashed in any way, Caspian makes top quality parts and it would have a decent value on that basis alone.
Just keep in mind that most folks wanting a custom Caspian would want a beavertail, extended thumb safety and upgraded sights over the King/Tappan's on it currently. Having that work done would cost quite a bit extra, so be mindful of that when considering a sale price.
This type of gun is one of the most difficult to place a value on. In the end, it's dependent on how much you think it's worth and whether that coincides with what the buyer thinks. Good luck and welcome to the forum!
Just keep in mind that most folks wanting a custom Caspian would want a beavertail, extended thumb safety and upgraded sights over the King/Tappan's on it currently. Having that work done would cost quite a bit extra, so be mindful of that when considering a sale price.
This type of gun is one of the most difficult to place a value on. In the end, it's dependent on how much you think it's worth and whether that coincides with what the buyer thinks. Good luck and welcome to the forum!