As a purchaser of someone's items, you may feel pretty powerless when it comes to haggling down to the price you want. But, at the end of the day, you are the only way someone will walk away having done business, meaning that you are the make or break for most flea market sellers. This gives you a lot of leverage when it comes to lowering the price, and if you know how to use that weight, you can end up walking away from every flea market stall with a transaction satisfactory to you.
When you start haggling, be firm on your offers. Don't waffle about how much you're willing to pay, or the vendor will be all over you and call your bluff. Start as low as you can without being unreasonable -- if you consider what they offer to be 100% of the price, offer between 40 and 60%. (This means that for a $10 item, you should offer between $4 and $6.) Don't act as if you're willing to come up on your price, or else you'll end up whisked to a higher price in no time.
Act only somewhat interested in the vendor's items. If you express too much enthusiasm, they'll peg you for a desperate buyer and use that against you -- with phrases such as, "You won't find this anywhere else!" Express enough interest to make them haggle with you, but don't act like you absolutely need their particular item.
Say you'll go somewhere else if they don't give you the price you want. If it's a handmade item that has more generic types, mention that you can always get something plainer at a store for a lot less -- or, at least, that you won't be supporting their business. When you use this against a seller, they usually cave pretty quickly, knowing that you're primed and ready to buy but are quite content taking your business elsewhere.
Point out another vendor selling a similar item. Essentially, you want to give the vendor the impression that they're a little fish in a big ocean, and that you don't need them to sell you what they have -- it would just be nice, because you happen to like them or their item or their attitude. Competition keeps prices down, especially in flea markets, where a sale or two can be the difference between turning a profit and coming up way short.
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