Advice needed

[Lee Levitt]

I have owned a '99 A6 quattro avant for the past five years. I bought it 
with 135K from Chris Semple; it now as 192K.

The car is black with black leather, with most options. I have done some 
upgrades to the car, including suspension (Hotchkis bars, Bilsteins), 
brakes ( Bira S3 front, B5 S4 rear), sport leather interior from a C5 
2.7t, etc.

It's a nice car...drives like it's 2 or 3 years old. And it's set up the 
way I like it.

It needs some minor work...three of the lower door panels are showing 
some rust at their bottom edges, and the left front fender is showing 
some rust on the bottom rear (near the door). For now, it's surface 
bubbling, no perforation.

Is there any reason I should not have this rust repaired? Does anybody 
have an educated guess on repair cost for the three doors and the fender?

I do have a preferred body shop, Anchor Auto, in Woburn, MA (Billy), who 
has done work on this car before (the other fender and door), and will 
approach him over the winter, with thoughts of having the work done in 
the winter or early spring.

By the way, when is the best time to have work like this done (when is a 
good body shop least busy?)

Thanks!

Lee