Someone Please Give Me An Answer or Alternative!?

Well, I wanted to sell some no longer wanted posters and White Stripes memorobilia on eBay (both of which are in pretty good condition), but my mother vetoed that plan. No matter how much I try to convince her that it will be okay she seems to want to just say no without even listening or considering (plus she listens to whatever her boyfriend says no matter how wrong he turns out to be). I need a solution on how to get these posters and memorobilia gone because they are taking away a huge portion of my room. Either a solution or an answer as to how to convince my mom that things will be okay, she seems to think someone is going to cheat me by asking for a refund for unreceived merchandise even though they have. I told her you can track your item and by eBay policy something like that can't happen without harsh concequences. Someone please help!!!