I am considering starting a seller account and starting directly with the professional membership. Is there anything to worry about if I start a seller account and not have any activity for a couple months? I'm curious if there are any kind of metrics that Amazon measures in regards to activity that might negatively effect my seller rating or anything like that if I don't start selling right away. I would like to have the opportunity to familiarize myself with Seller Central and see what the setup looks like before I actually post listings for sale. Any input on this would be much appreciated!