Hi. sorry, if it has posted already. I have concerns about selling/buying. this will be my first selling experience on this forum. Selling/buying processes are only between seller/ buyer or are there administrator controls? what I m concerning is that when I ship item to biyer's address, how can I be sure user will pay? or when buyer pay, how he/she can be sure that seller will ship it? I love this forum, loving my e reader, but I need money for educational purposes, that's why I want to sell it. but I couldn't find any information about how selling /buying will work? thanks