The gash at the bottom is such an easy fix, I couldn't see it costing over $100 to fix. Just get the shop to cut out the rust, weld new metal in the hole, grind it down, then prime the repair. You can then buy some rocker guard or trim paint and re-spray the panel.
For the mirror, go to a paint supply store and get them to whip up a spray bomb to match the paint code. Also get a spray bomb of clear coat. Remove the mirror and scuff the paint with some comet and the rough side of a kitchen sponge. Just do it just enough to remove the shine. Wash the mirror thoroughly and wipe it down with some denatured alcohol. Find a large cardboard box to use as a makeshift spray booth and get busy. Try to use several thin coats as opposed to few thick coats. After spraying the clear, you might need to wetsand but the mirror will probably look better than the rest of the car at this point.