I think I'd split this in two: the minimum amount of data you need to make an invoice and everything else.
Each business should only need to record what information it actually needs to make invoices and record the order for bookkeeping and keep that for as long as it needs to, in case the tax man comes around.
Everything else has no purpose after a set period. Abandoned carts, browsing history, support mail, marketing profiles - anything that does not have any value is just noise and should not be kept beyond what is strictly necessary.
For example:
You can keep a copy of every page someone has browsed since joining, for a one-time marketing activity, but beyond that. No need to store it.
It's all about defining the business requirements for what should be archived, stored, shared.