There is nothing like proper planning if you want to come out a winner at the end of your day at the flea market. Wear comfortable, loose clothing for the day. A bag or a cart is a must if do not want to be caught spending the day carrying around the items you purchased. You cannot discount bringing along a bag or a trolley for carrying items purchased.
Wearing good walking shoes is important to avoid ending your day because of aching feet. If you get tired walking it would be wise to walk to the very end of the vendors first and then work your way forward. You will have the privilege to choose first if you start at the back. In some locations flea markets are offered on weekends but in areas where the demand is high, we find flea markets even on weekdays. The diminishing number of visitors during the week leads to the correspondingly less number of vendors. Pinpointing the time of day to get a price deal will definitely lead to frustrations. It is possible to ask for a lower price than what the vendor is offering.

If you arrive early, you can choose from the available good before anyone else. This is the best solution if there are particular items you are interested in finding. Vendors are unlikely to negotiate on prices early in the morning, so prepare to pay a higher price.
The best bargains occurs when the end is about to end, when vendors are anxious to let go any remaining items they may have. Vendors would prefer go home with a heavy pocket than with a heavy load of merchandise. If you wish for lower prices try bargaining at the end of the day. Someone else might purchase it before you during the day.
There are different ways to negotiate the price of any given item. Simply ask the vendor the lowest price and try to arrive at a mutual decision. Try to offer a price and see if they would find it acceptable. If you have 10 dollars as the offer price, dangle the money and wave it your hand-this is often enough for them to close the deal.