The current owner printed a list of all the services done to the car since it was new. There were a lot of entries on the 5-page-long list compiled since the car was new, but nothing that I recalled looking bad. The description column had a lot of "Unknown" entries listed though. I'm not sure if this is common on other dealer-serviced Lexus cars, and it may even be that the tech was too lazy to spend time typing out what he did on the car. Many of these could be oil changes and tranny fluid changes, but the I am not sure. These "Unknown" entries were the only "cause of concern" I had. the current owner did not have any hard receipts because he said everything was documented electronically.
He said one of the important areas that needs fixing around 120k miles were the valves, which he said had definitely been done.
As far as the timing belt goes, isn't it a chain? Usually chains do not need checking until around 180k, or at least that is what I've known from past experience with other DOHC engines. I will ask the owner about this.
Based on my experience testing the car, I would say it is in solid, reliable shape; it really felt tight while driving it, and was significantly better than any previous SC I drove. The paint quality, the fact that there are almost no external blemishes, and the generally perfect state of the leather interior suggests to me that this car has been pampered as much as has been suggested by the owner.
I have called a Lexus dealership about inspecting the car. They are asking $122 to look at it. I haven't decided to buy the car yet, so spending $122 on a car I may not buy is not overly appealing. But I understand what you are saying, and I realize that you can never really know the whole story with used cars.