A successful garage sale accomplishes two things: it clears out unwanted items while earning extra money in the process. Avid garage sale shoppers love bargains and haggling, so before busting out the folding tables and dusting off your old CD collection, complete some advance preparation work and brush up on your negotiating techniques to ensure success.

Prepare for Those Die-Hard Hagglers

Hagglers can be intimidating if you've never hosted a garage sale or aren't comfortable with negotiations, but never fear -- with a little advanced planning, you can open for business with confidence. After you have chosen the items you are selling, do some research to find out what the going retail prices are for these items. Shoppers generally expect prices to be at least a 50 percent discount from retail prices, but serious hagglers may try to go for a 70 to 90 percent price reduction. Decide before the garage sale what you hope to get for each item - especially large items - and what your absolute bottom price would be. One main negotiation strategy is to look for uncertainty and hesitation, so coming across as confident and set on your prices is the best way to avoid being haggled into the ground.

Create an Ideal Shopping Atmosphere

Having a lot of traffic at your garage sale is a great advantage when negotiating, as shoppers are less likely to throw you low-ball offers if they see a large demand for your items. Attract customers by advertising your sale in advance, in online classifieds and on social media. Be specific in your ad and list as many of the items you are selling as possible. On the day of the garage sale, hang highly visible signs around the neighborhood to draw in customers. While setting up the garage sale, organize items in logical order to create a pleasant shopping experience. Group similar items together and organize clothing by size.

Elevate your garage sale experience by playing pleasant music over a speaker, or set up a folding table for a lemonade stand to encourage customers to hang around and spend more money. Be sure to have plenty of change on hand; all your negotiating techniques are useless if your potential customer has a large bill you can't break. To sell items quickly and encourage more purchases, offer a bulk discount on items such as books or DVDs; for example, price them at a dollar each or 10 for $5. Use pricing stickers on small, miscellaneous items to avoid confusion, but consider leaving the labels off of large or unusual items and let the shopper make the first offer. You may be surprised to learn that a customer who makes the first offer may offer more than you would have originally priced the item.

Use Timing to Your Advantage

Avid garage sale shoppers hit the streets early in the morning, so it’s a good idea to set up shop by 9 a.m. so you can cater to them and not miss any opportunities. Canny hagglers may appear near the end of your garage sale, when they believe you're willing to take much lower prices to just get rid of your items. If you have your heart set on getting a certain amount of money for an item, remember you can also list the item for sale on several classified sites after your garage sale is over. Though, if the main point of your garage sale is to clear out unwanted items, you can always mark down your prices - just announce to browsing shoppers that all items are 25 or 50 percent off their labeled prices and watch the goods fly off the shelves!

With a little advance preparation and confidence, you can negotiate your way to less clutter and more pocket money. If you know an item's worth, stand firm in your rock-bottom price, but stay as flexible as you can to appease hagglers and bargain hunters. A successful garage sale leaves both the seller and buyers feeling satisfied with the results.