Every state is different, you need to follow WVs requirements.
The dealer was in Ohio and only interested in selling the boat/trailer, wasnt up to him to meet WVs requirements, he doesnt sell here.
Is this the boat you posted about nearly a year ago?
Lets start w what you do have, what documents do you have specific to the trailer?
As a modern boat, I'm guessing a modern trailer, so probably not vintage or over 20yrs old?