It's not easy to get cash discounts unless you buy in bulk. For single purchases, the best negotiation tactic would be to ask for more at the same price - free upgrades
LOL, seems thisis almost becoming a bulk order....When i was playing arnd with the configuration tool , 2 more guys in my office decided to go alon, and now we have 3 identical orders...
Dell reps do negotiate... But you have to be hard bargainer... Speak softly & after all the heckling ask the person for more discount referring it to the floor manager... You will get good deal.....