Halserad: I have been a member of Audiogon for ten years plus. I look for forum posts from folks with zero feedback. (this means they are actually an audiophile) An ad has to be well done, and the payment needs to be PayPal for most buyers to ever consider a first time seller, so the buyer is safe, though you should also accept USPO money orders.
as a seller, you should not allow use of the buy it now feature. Then you can look at the prospective buyer's feedback and decide if you want to sell. If you use the buy it now, anyone can make the offer you must accept, even if they are running the Nigerian scam... Unless you are willing to jump through a pile of hurdles to get out of the sale.
And remember packaging the product and getting it to the buyer is your responsability. (i just had ANOTHER bad experience with a seller using a UPS store shipper, where the UPS store deliberately broke an expensive toy Wowwee Roboraptor, to fit it into a box at hand!! what crap service)
Anyway you should consider all yor options, like email when selling a product. contacting the potential buyers and discussing the sale is one extra way to have a great sale. If you just do the minimum, errors and problems can arise. Think of the buyer or (if you are buying) a seller as a family friend, and get to know them at least enough to feel like the deal is more than just an exchange of money.