There are many ways to pay. PayPal the most common. But fees are charged on both sides of this sale. Bank deposit which you do manually either by Internet or in person bank deposit or by debit or credit card over the phone or off their business website, cashiers cheque or eBay cheque. Ask them if they will accept other forms of payment if they only have paypal listed as payment terms. Alot will so they don't get hit with PayPal fees, although they have to say they take PayPal but are often happy to accept bank deposit. If they they say PayPal ONLY then I don't bother asking them or bidding or buying off them.
Always use PayPal, they might have a service which can withdraw cash from you personal bank account or check account, this way you have so sort of guarantee of delivery. Also the seller might allow COD or arrange a pickup point where you can pay them cash for the product.