Selling on Craigslist is almost the same as selling a house. Seller lists selling price, buyer offers a purchase price, usually lower than asking price, buyer and seller negotiate(counter offer(s)). If both settle on a price then the deal is done, if not wait for a new buyer.
Yes, once in while a buyer agree to seller asking price, but not very often.
Yes, once in while a buyer agree to seller asking price, but not very often.