I noticed there is alot of surface rust on the underbody of the car. Like the gas tank holder strap thigies, and the rear sub frame(or whatever the hell its called its like holding in the rear diff) anyways since the car is canadian and driven in canada it has to endure the lovely salted roads. So im just wondering is underbody rust a pretty typical thing on canadian vechile and should i not worry about it??? could it causes any major problems??? and is it expensive to fix???