Seems nobody could answer to this ... so I've asked Avis directly
Dear Mr. X,
Thank you for contacting us through the Avis website.
In order to use a specific AWD number, you have to be affliated with that
company (as an employee) or a member of the organization...You will have to
show proof at the counter to beable to use the discount. If you are not
part of the company or organization, and when you get to the counter, they
will charge you accordingly without it.
Look forward to assisting you in the future and thank you for choosing Avis.
Sincerely,
Avis Email Customer Service/USA
FAX: 918-621-4850
[email protected]