I don't mean to be a party pooper here but my experience has been.....
I tried garage sales and it is so frustrating that I just donate the sale items now and get a tax benefit. It is healthier for me, LOL
Whatever price you put on your items....expect the customers to want it for NOTHING. I had $50 Abercrombie jeans never worn and with tags still attached, I put a price tag of $7 and I was offered $1-2. Same thing with other good merchandise. I got so frustrated at people trying to dicker I just told people to leave my house and I closed up shop on the spot. I took everything to the Women's Shelter in Plano.
I was not trying to make a bundle of money but I refuse to just give it away to someone trying to deal.
Be prepared and make sure you watch the people that come in. Another reason we stopped is because a lot of "customers" are casing your house to see what you have. We put things up on the street away from our garage and house. I was appalled at the number of people who asked to go inside to get water or use the restroom. I am not kidding.
I wish you great success with your sale.