Buying Tip: Name your price.
It is not uncommon to see garage sales with their items out on display and no prices to be found. The average person will look for an item of interest and turn to the seller and ask, "How much for this?". This is the wrong question though.
When a seller does not spend the time to price their items, it is now your chance to name your price. It is pretty much standard for a seller to start their price high but in this type of situation, you get the chance to start the price low. If you find an item that you would like to purchase, ask the seller if he will take a price that you have chosen. This is the time to start low, there is no reason not too. If the seller refuses the initial price, simply raise it until to reach a limit that you set before hand.