It�s probably better to have a Premier account if you plan to sell a lot of things.
You can receive some PayPal payments without one, but sooner or later someone will try to pay using a credit card, and you�ll need to upgrade to a Premier Account in order to accept the payment. Once you�ve done that you�ll be charged a higher fee on every PayPal transaction, regardless of how it�s funded by the buyer!
The vast majority of buyers use PayPal these days, so you don�t have much choice really if you�re selling on Ebay. PayPal is good in some ways ... very quick payments, which makes it easier for sellers, and buyers like using it because it offers some protection.
If you�re selling high value items (same applies to any item though) you need to be especially careful. You must send the item to the address PayPal give you by �trackable means� ... this means it�s trackable online i.e. recorded delivery / Special Delivery or �International Signed For� if you�re sending it abroad; also the buyer has to be �verified� with a �confirmed address�. Confirmed addresses are only those of residents of the UK, USA and Canada at the moment, I believe.
If you go to the Ebay discussion boards you�ll find a lot of advice about this and similar matters.