I agree with chinatraderjmr. Very likely award tickets.. yes you may be successful and get a ticket for less than retail (if an award you won't earn any miles for it though). I get your position about risks paying off, but I wouldn't risk it in this case. UA has people looking at these ads too and if they find out who is selling them you'll lose your ticket and probably your money unless you're very lucky at recovering it. Isn't having a totally legal ticket worth the extra $147? Plus you'd earn miles for the flight.