I you know what you want, then also know how much you will pay.
Have cash or pre-arranged financing.
Make an offer, lower than what you are willing to pay. The sales man will say he needs to check with his boss and will leave you in a hot little box. The sales man will go take a leak and tell some jokes with his boss, then come back and tell you no. Make your second true offer and the sales man will then leave again. Give him 3 minutes and then get up and walk out and see his reaction.
Do all of this on the last weekend of then month
