....... check the servicing records and make sure the cambelt actually has been changed from a reputable invoice rather than just the sticker on the engine ........... the steering rake etc, well, if it suits you then i wouldn't find that too much of an issue . the aircon, well, maybe worry about that when you have more time and effort, it might be inexpensive or not.
You probably won't get a better car than a Ls400, just anticipate normal tlc needs over the years ahead ......
I would negotiate a price and just buy it, you're quite comfortable with this car and it might be a while before you find anything comparable for the money
Malc