Attachments are separate entities.
It will make our life so much easier and reduce the size of your storage if we an attach an attachment record anywhere.
See notes for a similar situation. A note on the Deal shows on the Account.
Do this for attachments. Show all attachments for deals, quotes, etc. also at the account level.
Allow us to ... "Assign Attachment to [account, deal, quote, contact, case]"
Very often the record for an attachment become obsolete and we have to download, attach elsewhere, go back to first record, delete attachment.
When we merge two records, it does not merge the attachments.
We are a software company with only 400 customers and we do this in our products.
I know you can do it.