That is from a dealer (Lexus Norwich)
But good advice all the same, have a look at the preowned cars on the Lexus site, and try to find any that are cheaper or better in any way and use that to haggle the price down if you definitely want this one.
To be fair, if you're not desperate, I'd go in, show interest in buying and say you'll pay £13k. If they don't accept, walk out and they'll probably call you back in a few days time to try and do the deal - worth a shot :)
Coming up to month end. They need to meet their targets.....bluff it out.
Malc