That's it, rear bumper changing time!
 

Okay after I bought my G35 sedan in October 2002, it has been rear-ended five times. None of my car's any other parts have been hit even once, all five times on rear bumper. The last time was this afternoon, and finally it has a two inches crack on the face of the bumper cover, so I think it is time to replace the whole rear bumper cover. Now my question is what is the most economical way to do it? Have the Infiniti dealer replace it and take it to independent store to paint it? Or it comes pre-painted already? And what is the estimate of the whole job, parts and labor? Thanks for the reply.

Mine is being replaced right now. The estimate for insurance was $692 with a new bumper from the dealer, including prep and paint and mount the new bumper. Insurance company came back with an estimate of about $550, using refurb of the bumper cover. Turned out my bumper cover was too badly damaged to re-use, so they are gonna put on a new cover. So that's about the range that you're gonna pay. They don't come painted already, so you need a paint shop to match the paint right. :(