First thing, go to an Apple Authorized Service Centre, but NOT an Apple Store. It must be a private business. Second, ask him what it will cost to repair the case damage. Yes, most of the damage is on the battery, so nothing can be done about that. As for the case damage, any sensible technician will charge you $10-30 to bang out the dent with a hammer, rather than order a whole new plate. As for the battery, either live with it, or replace it. If you order the battery as a service part (which requires sending them back the old one when you get the new one), it's cheaper. The authorized service technician can do that for you.