The algorithms are tied to your apple account, so it devalues on sale if you've spent a load of cash on new algorithms.
So, one tip to maintain its value on resale:
Open
an apple account specifically for the pedal. You'll need a separate email address. Then transfer the account
to the buyer (remove card details or use a prepay card, you make sure
the name on the account is something like "H9account - serial no. of
device" or something - is either changed or transferred to the buyer's name,
and lastly change the email address to theirs).
This is a stream of consciousness post, so I haven't thought through all the details. Any thoughts?