This Avis corporate account works for drivers under 21 without a underage fee. Corporate account AWD No. K148644 the company is Lesbern Limited. It is a property management company based out of London, but has branches in the US. Avis might ask you for company I.D. or a authorization letter. You can get one from the company. Just email Moshe Hackner thebestbroker@gmail.com and tell him you heard about the corporate account and would like an authorization letter. He has a organization for widows and orphans and asks anyone who uses the account to give a small donation.
You should create a wizard account with Avis and have the corporate account info in your file so they wont bother you every time you book. It is also best to book online to make sure you get the underage fees waved. Good luck.