How to perform subclassification - tags or correspondents or ... ?

[jhf2442]

Use case : I have multiple accounts within the same bank but would like to be able to differentiate the documents between them, for instance the monthly bank statements.

What would be the best way to do so ? Use the correspondent "bank" and add tags "account1", "account2" etc ? Or use multiple correspondents like "bank_account1", "bank_account2" ?
Same applies for e.g. my car insurance : same company but 2 cars -> how to assign the documents to the right car ?

My preference goes so far to the tag solution, but I fear an overflow of different tags (that are correspondent specific on top of it)

How do other people handle such constellations ?

Many thanks