I bought this off a friend a little over 8 months ago and what he did was just change all the login information, so whoever purchases it would provide an email address and password they wanted associated with the account and then the plus becomes theirs
Selling my PS3 which includes PS Plus, over 100 games, controllers as well as PS Move. Accepting reasonable best offers, hoping to sell soon. Thank you for looking! http://www.ebay.com/itm/281260559934?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649