It was a movie about like a brother and sister or a boy and a girl who are riding around in an RV, they have different powers. But specifically they can turn invisible... one scene
They go to a warehouse... ahhhh, it's driving me insane... it's so vague, I saw it when I was
Really young... possibly an alien involved somehow... I'm sorry, I'm just getting desperate...
-eddie

Try Escape from Witch Mountain.