Can't help you with the dealer or price, however in 3 years I've so far done 60k in my IS-F and all it's needed has been routine servicing and tyres.
Compared to the variety of other stuff I've had in the past, it's remarkably robust and reliable. I did take out the extended warranty, however the car is so good that it's only a safety blanket. I've got no intention to change the car as it suits what I do with it perfectly.
The most expensive service parts I've needed have been the brake pads and discs, however they are off the shelf Brembo items which can be bought for a lot less than paying for the same things in a Lexus box (which I annoyingly discovered about a week after I'd paid for my local Lexus dealer to fit the badged ones).
I did buy an 18 yr old range rover to lug junk around, after I got fed up with the amount of room. Particularly noticeable when retrieving student offspring in the summer holidays as well as trips down the tip etc. I think i'd been somewhat spoilt space wise as I traded a Land cruiser for the IS-F.
It may be worth noting that I did not even consider ditching the IS-F for something with more load space, I like the car that much - enough performance and you can't beat the reliability, or, in my own experience, the dealer service which has been spot on.
I am going to need to get some stone chips sorted out, combination of a few trips to Germany and relatively soft paintwork.