It's like buying a car you would never assume you are going to pay what they advertise it at....
I won't post the quotes from Humber but my first quote before I wanted to go up a size was for 5.5m Destroyer fully set up with A bars, 90hp Suzuki, trailer etc for 21K, this is before negotiation
Then i asked for a quote with non feedback steering all laid in, steering wheel, seat, console, raised anchor locker, extras such as orange GRP and usual extras such as grab handles, lifelines etc etc
5.8M Destroyer £7,544
6.0M " £7,780
6.5M " said £8000 ish! formal quote being done at moment.
I have been offered deals with the engine at cost with some companies, Humber should play ball also, they say 115HP is mid way and fine for the Destroyer 6.5M hull, range is 70-175hp
The above quotes are without haggling also...
Found out also the Destroyer hull has one chine the OP has two. Both dry boats, the Destroyer very capable in strong conditons the OP hull tweaked more again for when really pushing it - top end stuff with experienced drivers.