2003 Cadillac Deville Inner CV Boot

It is possible that they are trying to take advantage of her! ( They used to squirt oil on shocks and tell you they are leaking or poke a hole in exhaust pipes with a screw driver. )

Yes it is expensive ( labor ). The CV joint must be removed from the car to perform this. ( Front wheel assembly must be disassembled and ball joint seperated. )

Yes a leaking boot can be bad especially if it is a big leak. ( You loose all your lubrication to the joint and it will fail at the most inoportune time. )

You can check this out yourself if you or a friend are able or you can pay a token sum to have a garage put it on a lift and allow you to look at it yourself.
( Some garages may not allow you under the car for insurance reasons. )

This is what you look for: A leak means that grease will be squirting out of the hole and will leave a grease pattern where it was slinging out during axel rotation. Look for this band of grease in the axel area close to the transmission on either side.

Hope this helps and if it does, don't forget to help us keep helping others.

At 57k I would dought it, the grease is a greenish blue or brown look for it on the lower control arm and on the caliper of the side they were saying that was bad, jack it up and remove the tire to look may have some on the inside of the rim of the tire