Hello and welcome to Listia. You will need a verified address and account to be successful on this site. Here are two places to go in order to verify your account and address. It is confusing to have to go to two different places but that is how it has been set up
http://www.listia.com/account/verify http://www.listia.com/account/addresses This will help you with both buying and selling as most sellers require you have these verifications and if you are a seller it will tell buyers you are reliable. Good luck and if you need anymore help please just ask and I will be willing to guide you.