Changing CV Axle

One place is quoting me $250, another place is quoting me $420.

This is to replace the front CV axle (boots are torn). What could be the reason for such a huge difference in price?

You getting a new/rebuilt axle assembly or just the boots replaced?
Their hourly shop rate is - How Much ? And how much time are they going to charge you for? The dealership vs. private shop ? Dealership likely to charge higher shop rate and more for parts.