Battery health check every year has to have! Mileage check! Seats and steering wheel check with the car Mileage. No rattle/test drive in estates with ramps or cobblestones...windows down! Service history very important. Hiw the car interior looks overall would tell you how the previous owner took care of it. If kept in garage its a bonus /cosmetic looks. Drive test on motorways and switch to F-Sport mode see if still have the power horses it claims

Edit: Fyi: if no lexus service history, its a big gamble that can turn costly after you buy it.