Craigslist you list your items for the price you want. Ebay is bidding and may not get what you want out of it then there is shipping costs to consider. They both work well but most of the time my husband lists stuff on craigslist it is gone within a few hours so we have had better luck with craigslist plus there are no fees for selling items. Ebay charges fees after an item is sold but is very small amount and you need to use paypal to have people pay you on ebay. If you don't use paypal a lot of buyers won't buy from you.
Don't list your phone number on craigslist, otherwise you get a ton of phone calls after the item is sold. Use your email address only and email your phone number to the person you are going to sell the item to if you want them to contact you by phone. That way when the transaction is complete you won't get 100 phone calls asking if you still have the item. You may get a lot of emails but they usually just contact you once and if they don't hear from you then they usually won't contact you again as they will assume the item is sold. As soon as you sell an item make sure you go back on craigslist and list the item as sold.
If you do sell items on craigslist make sure you aren't home alone when they come to get it. You can tell them what time to come by or even meet them somewhere if you don't want them to come to your house. Since we live outside the city my husband will meet somewhere on the way to work as it is usually more convenient that way because most of the time they live closer to his job than our town.
We have also purchased a lot of items from craigslist and also got a lot of things free. Some things were in good shape, other items needed a few dollars to fix, just depends on what you are looking for. It is a great way to find houses for sale or rent, cars, boats, bikes, baby items, and a ton of other stuff. You can also find garage sale listings with some describing items they will have for sale.
Only accept cash for craigslist items. There are scammers out there with some sort of phoney moneygrams and don't accept checks from anyone either. Most people pay cash but you may come across someone that doesn't and will try to talk you into taking other forms of payment or talk you down.
What we do when we have several interested in the same item is let the others know that we will contact the next person in line if the one doesn't show up or decides they don't want the item. Most of the time the first person buys the item but a few times we have called the next person and they usually came right away or went to the same meeting place to get it. If you stay in contact with the person that is willing to come see your item right away you usually have a good and fast transaction.