Unfortunately they all are :(
Have you tried looking on Lexus website and finding one then asking Norwich to get it transferred down for your inspection. This happens quite regularly in the motor trade. That way they would get the deal and you would not be messed about.
Update - Birmingham have an SE for under £21k so should be easily negotiable with no p/ex. Lexus website for used is absolutley applaiing, you can't select model derivative and it;s so so slow ( goes through www.supercar.co.uk for some reason ).