I'd advise getting some advise from somebody who actually performs the type of
aluminum siding repair that you are seeking. House painters are not a good
source of information and most will not be very knowledgable in this area.
Also, the friendly folks at Home Depot aren't going to be able to "bend" vinyl
or provide good answers to your questions. Breaking aluminum to match is
certainly beyond the capabilities of HD - you need a long break (16' or more)
and a break that does angles other that 90 degrees or 45 degrees.
About 80% of the homes in our community (11,000 homes) had extensive siding
damage from a big hail storm last year. Most replaced their existing aluminum
siding with vinyl - some by choice and others because the exact match for the
aluminum was not available. But many stayed with the aluminum siding and got
new aluminum for the damaged side(s) of their homes. In some situations, the
new aluminum siding or the old had to be painted to match. Even for white
paint, the old and the new don't look identical. My aluminum siding was 38
years old and an exact match was available for both the siding and the corner
pieces. My color was too faded to match, so repainting would have been
necessary. (I opted for a vinyl replacement).
As I checked on options for fixing our home, I observed that 2 insurance
adjusters for our home plus several contractors all had different opinions
about the possibility of obtaining aluminum siding to match. So, I'd advise
that you check with more than one source. If you are lucky, you siding and
corner pieces may still be available.
Also, in every community there are homeowners who are upgrading their siding
and having old aluminum siding removed. The old aluminum siding is sold for
scrap. You may be able to work out an arrangement with a home improvement
company to sell you some old siding which they have removed.
Most siding installers work on a "piece work" basis. They aren't paid for
removing the old aluminum siding, but they are allowed to keep the aluminum
that they remove and they get the cash value for the recycled aluminum.
Working directly with such a crew might be a viable consideration. It would
certainly be less expensive since this would be an easy opportunity for an
installer to sell you a few dollars worth of otherwise scrap aluminum for $50
or so. Everybody comes out ahead that way. Several homeowners in our area did
this by watching for the start of work on homes with similar siding and
approaching the tearoff/installation crew. The work crew would carefully
remove a few long sections of siding, being careful not to crease it. They'd
set it aside and install it later for the second homeowner as a side job.
I Hope this helps. Good luck.