The first time ours cracked was 5 years ago, but the basics have not changed. The RV dealer,one on the largest in Florida, wanted 8 hours labor to remove the surround and replace the pan. 8 hours back then @ $110.00 per hour!!
My wife an I did it ourselves in 5 hours, and that included building a new support platform.
If you are even slightly handy, you can do it yourself.
Make sure the pan is propery supported. We found that the OEM supports were higher in the back than in the front and thus the pan sat off the support platform and flexed each time it was used, thus the crack.