Many eBay members have more than one account here, and often several accounts. If I remember correctly, you can tie up to eight eBay accounts to one PayPal account, and after that you'll need to start with the next PayPal account. But you can also have separate PayPal accounts tied to various of your eBay accounts. Just keep track of it all. lol
So you might want a main selling account for your general 'various' merchandise and then another (or more) selling accounts for specialty areas you're going to deal in, so you aren't combining two or more sort-of-opposing lines of merchandise and having it all together on one account. Many sellers here have several selling accounts!
Then you may well want buying accounts... your main one and perhaps a secret one that your family doesn't know about, where you can buy the gifts you're going to be giving them at special times through the year, and they can't get into this account and see what you're gifting them. 
And if you are going to be buying here when you see absolute below-value bargains to turn around and mark up and REsell here, you might want a special buying account to handle that effort.
And the *posting* account you use on these discussion boards, which may not have any (or much) buying and/or selling activity on it at all, but is kept primarily to use when you come to the forums to visit with folks here. There are many regular and LONG-time experienced sellers here on the discussion boards that you'd not realize until you get to know them, who have posting IDs with very little or no feedback, and yet they have years and years of experience and knowledge to share here.
Just keep track of yourself. It can get confusing until you get the hang of it. 
