What? No Upgradeable Listings

Just noticed that when a listing is created and a user wants to edit the listing there is no option for upgrade or downgrade of a listing.

Also, if a user was to upgrade or downgrade there would need to be a way to change the billing, lets say Paypal was the billing platform being used, the upgrade – downgrade would need to also modify the billing for the listing.

Sounds like a lot of work to change a listing… any ideas on potential work arounds for this little ‘monkey wrench in the works’?