This is not a plug for a program! I am just amazed how many people are looking to make a few bucks online and spend money on all sorts of programs and biz start ups when you can simply sell your stuff on Ebay. Don't have a garage sale instead open a store on ebay and start listing items.
The site is super user friendly just take your time and read it all before yo go hog wild listing. You can do this.
When you find something that you want to list first do a little research and find out what other people are paying for similar things. Just because you were told that the signed Nirvana picture is worth hundreds of dollars doesn't mean it is true. Be sure to look at the auctions that have actual bids on them and notice the time left. If that picture is going for 9.99 and there is 1 bid and 2 hours left to go it is probably not going for much more, but.... if there are 15 bidders and it is at $150 with 4 days to go you know it is going to be a good seller.
As far as starting bids, keep them as low as possible. If you are sure, from doing your research, that the picture is going to go for 200 start it at 9.99 and it will go up. Just keep in mind that auctions are a bit of a risk and you have to willing to give up the item for 9.99 if for some odd reason the market goes way down. But if you do your research right you are usually going to do fine. As far as putting a reserve on an item it is a guarantee on your price but you will loose alot of bidders that don't want to play the "how much is the reserve" game.
I bought a sweater and saw that one just like it in a different size was going for 112 with a few minutes left so I listed it at $9.99 and when it ended it only went to 52.00 I was a bit bummed but since I only paid $2 at a thrift store for it, it was a great profit. If I would have started that auction at $75 I would still have the sweater. So just keep in mind to keep the starting bid low, it also helps with your listing fees.
Now go list something and have fun making money at home!!!