Graeme, I would advise the following
A full Lexus Service which will include a Hybrid Battery Check and Warranty for it for 12 months and 10,000 miles
A 3 year Service Plan at a little bit more than £2 Graeme 🙂 and
Take out a Lexus Extended Warranty for 2 years at about £30 monthly which will cover you against Electrical and Mechanical failures. You can take these out every 2 years until the vehicle is 10 years old or has covered 140,000 miles.
Do enjoy what is a very fine motor car.