Wow!! 2 years ago I paid 13,500 for a 2014 IS300h that had 59,000 miles on the clock with full Lexus history and one previous owner. I can’t believe how well they are holding their value. Q1. Your offer would seem to be more than fair in my view, however I’m not in the trade so am not sure what values are currently. Q2. At 120,000 miles that will be a very big service, plugs and coolant as well as inverter coolant. Personally I would also have the transmission fluid changed before 100k, it’s more of a preventative rather than an essential. Q3. My 2014 is now sat at 174,000 and racks up about a 1000 miles a week without really breaking a sweat. I have a feeling the 12v battery is beginning to fail, and the suspension is now a little clunky so will need some attention soon. Aside from that it still drives well it’s still comfortable and still does over 50mpg on a run and 45mpg around town Sent from my iPhone using Tapatalk