Hi. If the car looks like it's been looked after, you know what I mean, and there is some Lexus service history and it drives as you expect (if not better) then go for it. I'm guessing it's not from a Lexus dealer but giving it them to service and check it won't do any harm (except your wallet but worth it).
I think the 400h is a 3.0 litre V6 (correct me if I'm wrong ) but still the Toyota derived V6 is a stonker of an engine and at 116k miles is nearly run in.