Thank you for the replies, checked service book fully stamped and dealer phoned the two lexus dealers in front of me to verify all service dates etc and also established cam belt/water pump done not long ago.
Having read one owners report of his car from the same supplying dealer/s failing its battery pack thought not even I could be that unlucky to buy the same car?
Just nerves I suppose after being badly bitten and this being expensive purchase for me
at least I have an independent garage that I trust to due all general work