Here is what you can do.
1) Trace back to who the trashcan belongs. (If Business, even better)
2) Send a letter to the owner saying their trashcan caused damage to your car and will pursue lawsuit if they won't pay the deductible. (Usually, all trashcans need to be removed right after the trashcan has been collected, Check the laws for that municipality and mention that in the letter).
3)Put the lawyer's office in the heading(just pick a random one from google)
4) a) they will ignore it or b) they will contact you that will pay u the 500 or 1000 deductible.
Make sure to attach a photo of the damage at the scene.(this will give them pressure that you have a proof)