A few questions regarding opening a store

[print-stuff-and-things]

Hi, sorry to ask these questions, but I need advice form real people!. I have to open a store because my fees are getting too much. I'm a bit confused about a user id/store name - if they aren't the same, how would previous buyers find my items, can you sell in the store and also under the username (are they separate things)? Are the paypal fees the same with a store? Is there any difference in how my items will be shown in a search? If my listing is usually 1st (for instance) if I open a store, will the item still be 1st? Is there anything else I should know!? I'm very apprehensive to do this... I've been selling for many years and am very used to the way things work with a plain old user ID, will I be up all night trying to work out how to customise the store, relist, find my buyers email addresses etc, etc! Many thanks