I'm not sure, but check MouseSavers Rental Cars/National page. Mary goes through what the various locations are. I think that the LAKE BUENA VISTA location might be a rental desk in a Downtown Disney resort, possibly the Hilton?
The Dolphin location's code is: ORLR13 .
Orlando Airport's is: MCOT01 .
Magic Kingdom Car Care Center(near the "car turnstyles"): ORLR02
Shelly, you can get a complimentary/no-cost shuttle to the Car Care Ctr location from any WDW resort. Arrange this with the front desk the day before, or arrange it at least early on the pick-up day. For instance, we called early in the am for our pickup to be around 2pm that afternoon.
A couple of tips...
Play around with various pick-up locations, sometimes it is cheaper with National to rent from an off-airport site than renting directly at MCO. Take Magical Express directly to your resort. After all, it is included in your room rate.) Then rent you car from either the Dolphin or the MKCCC.
Even if you don't need the car for 5 days, take a look at the weekly rental rates. Often a one-week rental can be cheaper than a four day rental.
Take a look at MouseSavers' hints/tips for renting cars and see if there are any special discounts you are eligible for (like
AAA or Entertainment Card or whatever). Just this past week (August 10-17), our Entertainment Card rate(+ the $20 off coupon) cut our rate in half(from over $300 with no special rates/codes/coupons to $142 including all fees & taxes).
good luck,
agnes!