Thanks very much for your quick response, Billy! I did some research on timing belt on low mileage old cars. It seems that heat has a much larger impact on timing belt than age. Because timing belt is "hidden" under the timing belt covers, which are hidden under the hood, weathering of the belt with age should be minimal. Plus the car has been sitting in a garage when not driven. So I agree with you suggestion and I shouldn't worry about the timing belt until after 100,000 miles (probably even after 125,000 miles). I realize that the LS400 timing belt is extra strong. Your opinion made my decision making much easier. By the way, your Lexus cars look very beautiful in those pictures.
Someone else is selling a 2002 LS430 Ultra Premium package for $10,500 ($3000 more than the 1996 LS400) with about 100,000 miles on it, timing belt done around 85,000 miles. However, the seller was not willing to provide any other maintenance history. Which one would you go with? Those air struts big dollar items.
Attached are some of the pictures of the 1996 Lexus LS400 on the ad. The car looks almost identical to yours in the first picture.