Parking is free if you are staying on-site. The AAA parking area is separated from the general parking. It is "supposed" to be closer. While the AAA parking is right up front, at MK & AK, it is off to the side. We usually drive to the parks so we use our AAA parking pass most of the time. But ff we are planning on getting to MK at opening, we'll sometimes use general parking rather than AAA to avoid the walk to the side when leaving.
Have a terrific trip!