What a question?! Maintenance requirements vary from model year to model year.
Which year model is your Camry?
Are you sure that the dealer recommended replacing timing belt?
From 2002 model year, Camrys use timing chain instead of timing belt. Timing chain is considered life time unless sth. irreguler happens.
For maintenance, you can follow the owner's manual.
Gear oil? I guess that should be the automatic transmission fluid. If dirty better do a service.
I can see if the brake fluid is dirty and needs a service through the plastic bottle on the brake master cylinder, or the dealer guy just wanted to sell you some extra service.
The main point is whether or not your car needs these services. If yes, do it. You spent some 20K for a Camry, why don't you hesitate spend a little money to try to keep your it relatively trouble-free and prolong its life?
