Let me guess-
Do you have a written sales contract detailing how payment and transfer of title will take place?
Do you know if the seller is actually the legal owner and has a title in his name ?
Did you use an attorney to close the deal ?
Read through this link from the WV Dept. of Transportation. You will see that it is illegal to buy or sell a mobile home without transferring a title.
Mobile Homes, House Trailers, and Manufactured Homes
You're likely going to need an attorney to get the title transferred to you, although I suspect your seller is either not the owner or has no legal title.