How much should I really pay for the new Golf Estate?

I want to buy a new Golf Estate 1.4 TSI SE, but want to haggle for the best deal. The list price is £20,620, and with some extras is £21,503. I will be trading in my 2004 Golf Estate 1.6 SE, which has...

Where might I get a discount on the new Volkswagen Golf estate?

I'm keen on the new Golf estate, which, according to Volkswagen, can be ordered from July. What are my chances of negotiating a discount?