It’s true that one person’s trash is another person’s treasure.

Just look at how many garage or yard sales you see on any given weekend and the number of people who attend them.

Betty Patterson, Lawrence, looks over some clothes at a garage sale in Lawrence. Each weekend, bargain hunters flock to the sales, hoping to find a good deal.

Garage sales are a great place to go looking for a bargain or treasure. You never know what you’ll find. That’s part of the thrill of the hunt.

What are some tips to be a successful seller and buyer at a garage sale? The two camps often have different agendas the sellers want to get rid of their stuff while making money and buyers want to snap up deals at rock-bottom prices.

But there are also many times when a seller and buyer will mesh wonderfully. The seller wants to get rid of as much stuff as possible and prices things so they’ll practically walk away from the garage and there are buyers willing to take them.

Chris Heiska, whose Web site, www.yardsalequeen.com/, is filled with practical tips, suggests pricing items a quarter to a third below what it could fetch if new.

“Of course, there’s a lot of leeway in there because nobody cares if you paid $50 for your old physics textbook or your old bowling ball,” said the Maryland resident, who confesses that she’s addicted to garage and yard sales. She only missed one weekend of sales after giving birth to her son via an emergency Caesarean section a few years ago.

Heiska is a serious shopper. Every Saturday she goes bargain hunting sometimes for items for her family and also to buy things to resell on auction sites such as ebay. Her best bargain for herself was a children’s wood rolltop desk for $3 and her best resale item was a doll high chair she bought for $15 and sold online for $227.

Patty Hill, Lawrence, scrutinizes a popcorn popper at a garage sale last weekend.

Dick Wells, author of “Your Hidden Money! How to have your own profitable yard, garage, block or estate sale” ($4.95, Aztex Corp.), suggests using discount stores as a barometer for prices and marking items below that.

Sellers should always have in mind the lowest price they’re willing to sell an item for but don’t volunteer it to buyers.

Buyers are “always going to grind you and expect you to discount,” said Wells. “That price you put out there …is your recommended retail price.”

Said Heiska: “I might mark (an item) $8, but I’d be willing to take $5. If someone pays $7, that’s great, but $5 is fine, too.”

Heiska said when she’s the buyer she sometimes negotiates, but also knows what’s reasonable and is willing to pay the sticker price if its good. Wells said buyers should always try to negotiate. What do you have to lose, he asks.

Heiska said when negotiating, get the other person to name their price first.

“It doesn’t matter if you’re the buyer or the seller. The goal is to get them to name their price first,” she said.

For instance, if an item is $10, Heiska says you should ask if they’ll take less for it, but don’t say something like $8 if that’s what you’re willing to spend since maybe the seller will come down further than that.

Heiska said presentation is important because people don’t want to rummage through your old boxes that are full of cobwebs.

But Heiska also said to use common sense.

“Don’t spend two hours polishing something that you’ll ask 50 cents for,” she said.

There’s also an unwritten rule that people don’t want to buy all of your junk.

“If it’s ready to be picked up by the trash collectors, leave it for the trash collectors,” said Wells.

Among items that usually sell well at garage sales: in-style clothes, baby and kids items, household items and tools.

Whether you’re having the garage sale or shopping, Wells said, the most important thing is to have fun.

And find some great deals.