So Can I Offer You A Helping Hand
There are a number of Government Publications and websites that offer guidance on importing a vehicle, if you feel confident in tackling it yourself "pull away". For everyone else I'm not going to try explaining the process in detail as I hope you'll be asking me to do it for you, however I will give some brief advice:-
There are two very separate issues to deal with and it must be in the order of HMRC Customs clearance first as every vehicle has be on the NOVA system before tackling the other Government bodies responsible for registration. dependent on the vehicles history the DVLA, DVSA and VCA.
The best piece of advice I can offer is always "get your ducks in a row" you must have a properly thought through plan, or get professional advice, although this applies to any import it is especially important with a new vehicle. As HMRC will be normally demanding VAT in addition to any applicable C&E Duty, plus the documentation must specifically confirm the paper trail of purchase, payment and that the vehicles is new.
MODERN USED VEHICLE
There are two very different routes for a used vehicle dependent on if it was previously registered in or outside the EU. You'll need the previous registration documents and either Type Approval (COC) for vehicles up to 10 years old, or possibly individual testing (IVA).
CLASSIC & HISTORIC VEHICLES
These can be easy or hard, a typical USA import with a current Certificate of Title, transported and HMRC cleared by a competent Shipping Agent, and your half way done. But if they or you forget to "cross all the t's and dot the i's" things can go haywire. I'll be happy to pass on advice and contact details of experienced and reliable people, I have used myself.
BARN FINDS & UNDOCUMENTED VEHICLES
Usually these are the most difficult and time consuming registrations, each has its own problems. Normally I can only give an approximate cost as until the specific issues are investigated it's impossible to estimate the time scale and amount of work required. With these registrations once the history of the vehicle has been explained and any available paperwork examined, free of charge, I will then ask for small basic payment just to cover initial expenses. I'm sure you'll appreciate with a vehicle that has limited or no documentation, there unfortunately can be no absolute guarantee of success.