Trip planning for elevation limits

Thanks, We are assuming 7000 is no problem, I drove D out to Mount Mitchell in NC el. 6684, when she got out , walking more than about 50 yds started winding her. Just riding in the truck she was fine. We are trying to get house sold and to roll for a couple years and were concerned about having to get too high, Had assumed someone had an app for the tablet or phones, and local knowledge for an area is always welcome.
Russ