Hi Cobbers.
You say you've tracked down the culprit, well done, but have you got acceptance of responsability in writing. You see, when the culprit see's the bill they might just ignore the situation and even proclaim inocence. I must admit that I did get an admission statement from one bloke and my insurer was actually amazed that I'd managed to get such a statement as all insurers tell their clients not to admit responsability even if it is blatently their fault. They were concerned that I'd not forced the statement by any form of "intimidation".
I personally would press for a replacement panel. Unless the repair shop knows exactly what they are doing, you could be left in a few years time with a repaired panel that show it. You could get paint pealling or even after the sun has bleached the panel, any fibreglass repairs might become visable.
As John has pointed out, your storage facility should have insurance cover for damage on site by third parties and so their policy should come into play on this one.
However most important of all, get any verbal agreements backed up with written confirmation and these confirmations counter signed by all parties. Just incase you need to rely upon these commitments in a small claims court at a later date.
Sorry to sound so sceptical, but I have worked with people in management who will not put anything on paper or E-mail just so they can use their "get out of jail card" of "when did I say that, I never agreed to that"!!
Hopefully your case will go the right route for you.
Regards.
Steve L.