Alamo. If you are a Insiders member and check in at the kiosk, the kiosk will try to charge you $10 a day. Just skip it and continue to check in. WHen you get to the exit booth in the garage just ask them to add the spouse and it will be free. Just have your spouses drivers license ready to show the agent.
Oh the Insiders club is free and they offer better discounts and higher amt coupons to their Insiders members!!!!