Preety sure maintenance is very similar between all three especially since the F Sport wasn't introduced until the 4th Gen. However, I think driving style and changes you make to it can increase cost of maintenance. For example when I owned my GS I went from the stock square setup to a staggered setup which prevented me from being able to rotate tires. I was also heavy on the throttle so I had to change breaks more often than someone who babied their car.The pricing's exceedingly similar to each other from what I've seen between the GS, IS, and ES on the NA used market for similar model years. I understand that parts, maintenance, among all the other things I'll need to worry about will end up being very dependent on the model I'll end up with. ES is seemingly the cheapest to maintain, but I'm not sure how that holds up relative to the GS or IS for that matter.