Any tips appreciated…
How do I make them knock off the prices to the best possible extent?
Tell them you have their family imprisoned evil:
Agar tum aapni maa ko zinda dekhnaa chahate ho, to mujhe bada discount de do…muhahahahahahaha
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 
also ask them to cut the taxes , octroi et all and tell them to manage it in the tag price
^ Cutting taxes + free shiping is the least you can expect.
Rest depends on your rep and your rapport with the rep 
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…
This should help me get some leverage 
Its pretty hard man.. 
..
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…