@BUG4LIFE Hi Rhys
For me I always buy on condition many will say mileage is not so important and these cars do wear well, but the truth is mileage means wear ! So try if you can afford it if the car is a keeper look for the lower mileage buying the best will cost but it's more of an enjoyable ownership experience.
There really are very few common problems, water pumps can weep they do not fail most would probably have been done by now, discs and pads from Lexus are expensive so check the life left in these.
The front tyres wear on the inner shoulder another check point, there is an after market cure that some on here are starting to fit.
There has never been a reported instanceof engine/gearbox failure or any major component the odd steering rack and radiator but again this is very rare.
The whole car just seems to hold up very well indeed and they really are a wolf in semi sheep disguise, they are quick but still relatively economical, and to sum if you come across a really shabby uncared for example unless it's very very cheap walk away, parts are expensive as one would expect for a car that was £60K new.
Remember there are only about 212 left in the UK so you may have to travel for the right one.
If you find one I'm confident that someone on here will know something about the cars past.
Big Rat