Hi Anne,
I know you had many responses already but I want you to know that I like good stuff and I haven't been shopping in garage sales lately (in a long time I should say) but if I am willing to pay $80 for a gorgeos pair of pants in Banana Republic, then I will be more than happy if I can find one at a garage sale for $15 or so. The problem is that the people that goes to your garage sale might not be able to purchase your pants because of size or other matter like diferent taste in color, etc so it is hard to find the right customer for your specific items.
That said, I would say, if it is something that it is still in fashion, let's say in the last year or so or a classic that looks like new (jacket, raincoat, etc) I can't say $2 is enough, I would prefer to give it to charity rather than selling an expensive item for a couple of bucks.
If you go to a store that sells use or defective merchandise, you ralrely pay $2 for an item that worth a lot more.
Check your items carefully, make sure they don't have any stains, or wear or tears and if they look like new, think how much you would pay for it if you have to buy it again and take a few extra bucks for the size and taste issue (fewer customers).
A bit of advice, have a cordless phone with you and never leave your cell phone or keys and car keys unattended! I have a frind that did a garage sale for the first time and while looking for change or answering the house phone, left the keys and cell phone outside, and where stolen, you can imagine the headhache after that. She said she'll never do a garage sale again no matter what.
Keep change handy but out of sight, like a plastic pencil box under a tablecloth or something like that or even better a belt purse where you can carry with you, don't get distracted unless you leave nothing important outside. Not even if someone ask you to use the phone or for a glass of water. Just say sorry but can't leave the place unattended or take all the important things with you, keep everything handy or in one single bag that you can carry with you.
Keep batteries handy if someone ask to try a toy, again so you don't need to go inside. If you post local signs, the risk of being stolen are less but if you go newspaper and public lists....you'll get a ot more people but be careful!
Best of luck!
Mariana