Hi EMT, it is really easy to do, as Dutchie said. You will expect to pay the tax on the items. If the boat and trailer are manufactured in North America, you will not pay duty...but if manufactured elsewhere, expect to pay duty.
If it is a brand new rig, I don't believe you will need to have the inspection done in order to register it, but I could be wrong.
Even on a 6000-8000 dollar rig, the savings can be up to $1000 even accounting for the cost of your trip. There are some smokin' deals to be had on craigslist anywhere in the northwest along the coast, tons of boats out there.
Good luck