A few people have been scammed on the site, Only use paypal to pay for items for sale by other members. If they will not use paypal, its likely a scam NEVER SEND E-TRANSFERS OF ANY KIND.
FWIW, my 2012 NC began having this issue about a month ago. Both A and B trips were either randomly resetting and/or would jump to a lesser number (i.e. I'd be at 146 then all of the sudden it's 125). I removed the instrument cluster from the bike and realized that there was something rattling...