I'm the complete opposite.
I own a small tree care business and folks will try to work me down as well. It doesn't bother me because I'm the same way. Nobody wants to pay more for something than they have to. Back in '98 I bought a wood chipper that was used for demo purposes. It listed for $30,000. I offered the dealer $25,000 because it had 4 hours of demo time and quite a few scratches on it. He came back with $26,000 and we were both happy.
I wheeled for the mandolin I bought this past summer as well. Being a small mom and pop store, it was easier than dealing with a large chain. It listed for $600 but had a severe cosmetic blemish that was repaired quickly and wasn't meant to hide the fact. He had it marked down to $475. Here's the thread. http://www.chordie.com/forum/viewtopic.php?id=24092 I don't know what a large note is in the UK but here, $100 bills get the attention of retailers. I offered him 4 and he took it.
Personally, I don't feel it would be out of line to ask for a discount on a demo model. Also keep in mind that credit cards have fees paid by the shopkeeper. Cash goes a long way to getting a better deal.
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