Depends on so many factors, but, no point even considering if the boat is not C.E. marked to comply with European Recriational Craft Directive (applies to new and used). As this is most unlikely unless the boat was built for export I would drop the idea now unless you are US service on temp posting to UK.
When I imported Trim Tabs from the states 18 months ago it cost 5% import Duty and 17.5% VAT on top of that.
If the carriage goes on the same bill you get to pay VAT on that too!!!
I paid the carriage seperately on another credit card and the invoice on the box only showed the purchase price "all fully inc," so did not have to pay duty on the carriage.
It's been a while since I brought a boat in from the States, last time was a 30' powerboat. Shipping would be around $2,000.00, but in addition to that you would have to pay for dockage, craneage, wharfage, handling, CAF ( currency adjustment factor) insurance and around 2% duty, and then VAT on top of the entire costs. As for CE marking, You could just ignore it like a lot of people do. Although I of course would not reccommend it as I'm a law abiding citizen.
If you study CE marking in detail, you will find that a lot of new boats currently for sale do not meet the rules, simple things like legends on switches, warning decals etc are probably the most common, although horsepower ratings are quite interesting.
If boat manufacturers aren't sticking to the rules, it makes you wonder whether you should worry about them yourself.
The CE-marking has to be applied by the importer: person who brings the boat on the EU market. IOW: you.
Classify it as a class D (sheltered waters) and go for self-certification. Draw up a declaration of conformity, and have a builders/importers plate made. Presto: instant CE-marking.
It might be difficult selling the class D boat later, though.
I have just brought in a 1993 Searay 270 Sundancer with a brand new mercruiser engine installed for £18500 all in. Used an export company in the States took 6 weeks and no hassle, boat even arrived in Southampton on time and cleared customs in 1 hour. 10 boats were on my ship from St.Petersburg so someone must be buying them, when I was at the docks all boats appeared to be going to private buyers not dealers, mainly Searays, Bayliners and a couple of tasty Formulas. Break down of my costs as follows. Even got a full tank of fuel and a full valet and over a grands worth of top range chart plotters and fish finder in the price, boat is gleaming and looked new. Only thing needed doing was change the shore power.
Basic Boat £12000
Shipping £3000
Vat and import £2900.00
Paper Work and dock charges £180.00
Transport from dock to Marina £250.00
Cranage at Marina £110.00
Contact me if you want to know more or have some questions.