Haggle when shopping it's a must!
If you shop in Tunise on the street or in markets do haggle for a better price. You're expected to do so and you'll offend the shop keepers if you don't or be considered a stupid tourist as they'll rip you off your money. It's fun, just try it. Always make the shop keeper tell his price first. It will be over the top. You then have to say a sum which is a third of his price. Usuallly, you won't settle for it but afer a few minutes of haggling you'll come to something acceptable for both of you. Don't be offended if they call you a criminal it's just the part of their fun and drama and don't hesitate to walk out of the shop if the shop keeper refuses to come up with a reasonable price. Most likely he'll come running after you with a better deal.