If you want to help folks, do it, don't just tell them what you look for. The key is looking for what you know. Also, go with your gut.
I hit estate and garage sales every week. My average e-bay sale is over $46. People specialize in kitchen/dinning ware, sporting goods, games, jewelry, electronics, cameras, clothing, paper, furniture, etc. As you become successful finding valuable items in one category, if you have time, expand. Do some research. Make it fun. Take some risks.
Knowledge is power. If buying pots and pans, know which one are worth a lot and ignore the rest. If you specialize in Jewelry, carry a loupe. If you look at kitchen knives, learn what to look for on the knives - some knives of one brand sell well while others won't sell at all. Just because something is old doesn't mean it is valuable, and just because something is fairly new doesn't mean it isn't. Listen to what others say and watch what they buy - learn from it. I sold $1.25 worth of old lamp parts for $65. I sold a $1.50 shirt for $760 and an $8.00 helmet for over $1200. Always ask for what you want. Make cards that indicate your specialty. I am a camera collector. I hand out cards all over the place. I purchased a collection for $2,000 and have made over $11,000 on it so far. Sure, you will be offered junk, and you can say no thanks.
Find out how estate sales work in your community. Are there lists to get on? Does the person running the sale give out numbers? Do you have to stand in line for a great sale for 10-15 hours before it opens? Chances are that garage sales are open before the time in the notice. If what you are looking for is a popular item, you want to be there first, and don't be surprised if someone knocked on the door at 6:00 am for a 9:00 sale. (I don't recommend it.) Oh yes, always be nice, it will pay off.
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