Janet,
they have changed the policy about
scooter rental companies just dropping units off....
now only certain companies can do that. They must be a preferred provider. If they are not, and Disney finds an ECV unit just 'sitting around', WDW now retains the right to confiscate said unit and the rental company must pay a fee to retrieve the unit. There is alot of speculation as to why this changed but one of many thoughts was that units were being damaged either by a guest or WDW and each was pointing the finger at the other when the rental company questioned what happened. And finally WDW said enough. So I'm not sure Bell services is still willing to charge ECVs anymore since they won't accept them from many of the rental companies. If you (a renter from a non approved rental company) leave it at bell services (luggage dept) to be charged and they change staff, it might be too risky that they confiscate it as 'abandoned'. I wouldn't do it.
I plan on checking into this when I go back to POP in January. But I am thinking ECV users are going to need to charge ECVs in their room now not at bell services anymore.