If you have the boat title and registration it should have the boat serial number on it but you still will have to prove ownership with either a notarized bill of sale, act of donation or act of heirship. DMV would require the same, try to read the trailer VIN number If Ohio doesn't issue trailer titles you don't need one, just proof of ownership.. If you haven't talked to WLF and the DMV yet do it and explain the situation. I just sold my boat to a guy in North Carolina. all I sent was a notarized bill of sale covering both boat and trailer and the signed trailer title.