Verify the price before you sit down in the chair - make sure they know which service you want. I've heard of and experienced charges that we didn't agree to ahead of time.
If you don't think it will be corrected, don't book. I wouldn't blame you.
Voyager goes in right behind Mariner on Nov 26 it looks like....for the same length of time (20 days) so perhaps she is getting the same major workover.