What's lurking under that awful paint?

We started the process of removing paint.  As suspected, we definitely have some challenges on the rear wheel arches.  We did not expect though to find significant body damage to the passenger rear fender by the tail light:

We also found the car had been side swiped on the drivers's side, impacting the front fender, door, and rear fender:

The driver's door looks like we can hammer it out and use a very thin layer of filler.  We have a patch panel for the front fender.  But the damage to both rear fenders, including the arches, is troubling and could be expensive for patch panels and/or take a lot of time to fabricate patches.  We are looking into options to address these concerns.