I wouldn't be too concerned. Lexus performs very highly in our Satisfaction Index (www.honestjohn.co.uk/honest-john-satisfaction-inde.../) with the IS being one of the top three cars for reliability. The CT shares a hybrid system with the Toyota Prius - a car that's popular with taxi drivers. We've heard of numerous examples covering hundreds of thousands of miles without an issue. The main thing I'd look for is a comprehensive service history. If it's been well-maintained, I doubt you'll have an issue.