On any given Friday or Saturday from spring through fall, Judith Kean of Two Harbors, Minn., likes to hit the garage sales. It's been taking a whole lot longer to hit them all since the economy tanked.

"There used to be six to eight sales every weekend," she said. "Now there are 15 or more."

While the number of sales are up, the quality of the merchandise has taken a dive, Kean said. She and other experienced garage-salers attribute that to newbies, who are looking to make money by trying to sell possessions they might have thrown away or donated to charity in the past.

But you can avoid that pitfall if you know what you're doing. So, for buyers and sellers new to garage sales, here are tips from Dollars & Sense, as well as from readers.

IF YOU'RE SELLING ...

Price low. That should be the goal if you want to get rid of stuff. For pricing guidelines, visit thrift stores, not eBay.

Use plenty of signs. Keep signs on every other block and every corner where a turn is required in the city (a half-mile apart along longer stretches in the suburbs). Make sure the address and sale dates are large and easily readable. Add balloons to attract the eye.

Sell with others. Doing it alone is too much work.

Sell to early birds. But charge extra, say a $10 "tax" for a purchase.

Keep it short. Make the sale one or two days, but not three.

Promote yourself. Advertise as much as you can in the newspaper and on Craigslist, Facebook and bulletin boards.

Cut prices. Advertise that on the last day or last afternoon, everything is half-price.

Offer details. Be specific about sale items in an ad, such as a leaf blower, musical instruments or furniture.

Be friendly. Greet everyone who comes to the sale.

Group small items. And sell everything for $1 or more to eliminate coins.

Plan ahead. Take the spring and summer to collect, price and box items to sell in the fall.

Choose the best hours. That's 8 a.m. to 5 p.m. Thursday, 8 a.m. to noon Friday, and 9 a.m. to 3 p.m. Saturday.

Donate leftovers. Call ahead to have charities pick up what's unsold. Check out the article "Charities that offer pickup" at www.startribune.com/dollars.

IF YOU'RE BUYING ...

Don't bring your purse. Leave it in the trunk. Keep quarters, ones and fives in a pants pocket or jacket.

Cruise around. Check wealthier neighborhoods for better-quality goods, but haggle if prices are too high.

Shop later. Browse in the late afternoon or on the last day for the best bargains. Any offer is fair near closing time.

Play it safe. Skip cribs, mattresses, car seats and hockey helmets due to possible safety concerns.

Set limits. If you're concerned about overbuying, set a limit for yourself on spending or the number of items you can buy.

Leave your card. Ask to be called if an item remains unsold and the seller is willing to accept your price.

Tips contributed by Laura Bahr of Lakeville, Terri Gilson of Wayzata, Dave Hoang of Blaine, Judith Kean of Two Harbors, Shelly Lagerquist of Lakeville, Carlos MosBrucker of Eden Prairie, John Schroeder of www.gsfever.com, Anna Sheelander of Stillwater and Mary VanderLeest of Minneapolis, as well as Good Housekeeping and www.stretcher.com. John Ewoldt • 612-673-7633 or jewoldt@startribune.com. If you spot a deal, share it at www.startribune.com/blogs/dealspotter.