I DO body work. The bottle jack will do the job or you can rent/beg/borrow/buy (HF has a serviceable one) a PortoPower (trade name for Blackhawk but widely used in the trade) and use the attachments to push the panel back. It'll take a little time as you'll have to over stretch it and determine how much it springs back. Also, when you have the lower back panel (that's what it's called) under pressure, tap lightly on the wrinkled areas to relieve the "memory" in the sheet metal. If you can get a template off a straight body (just trace the unbent one on cardboard and cut it out) it makes it a LOT easier to get it back to the right shape.

You can also carve out a block of wood to roughly fit that dent in the rear quarter and push that from inside the trunk to get that area back in shape - hardwood works best (old pallet skids are hardwood and free). A tip - drill a hole in your hardwood block for the jack's ram - it'll keep the block and ram in alignment.

EDIT: The areas you pointed out should work fine as push points. Any time you fold sheet metal it gets stronger so those 90* bends ought to be pretty stiff.

After that it's just finishing and painting. If you can't or don't want to handle that, MAACO can do a decent job if you do the prep.

Dan