I return.
Went to the dealership this morning. Upon arrival, we realized they already replaced the brakes, all rotors and pads were brand new. Not OEM quality equipment, but still, new brakes.
Took it inside, upon on a nice lift, and then they left us. Salesman went away, even the mechanic went off to work on another car, not even a babysitter, full toolboxes ahead of us if we needed/wanted them.
We didn't end up using tolls, since the brakes were replaced, we had no cause to yank the wheels off, and by walking under it, we could see the suspension. There's some rust along the exhaust system, but that's normal, everything else is in great shape, O2 sensors have been replaced. I see how the newer G35 (07-08) gets another 20 HP; reduced backpressure by using two independent exhaust routes.
Dropped the car back down, everything we wanted to investigate checked out fine. Low beam xenons are confirmed as being the top capsule section, the lower is the bihalogen multipurpose. No problem.
Nav seems to work fine, CD player works, lights work, tons of brake lights all over the place, et cetera.
Tires look pretty fresh, one of them has two nails short in it, they're just gonna put a new tire on there. No mention of shaving, so I guess the other tires are that fresh it'll be okay, something I'd like to try to confirm.
They'll try to find an owner's manual and some floor mats, the driver's door weatherstrip will get reattached, and the body molding stuck back on. By the time we were leaving, they were already starting to try to buff out the marks on the headlights.
I'd been a little uneasy about this dealership at first - not after seeing the brakes there, not after they left us to look the car over.