My Toyota Tacoma doesn't have a locking gas cap, how can I lock the cap itself or the door that covers cap ?

Question

Is there some sort of tape I can put there that an unauthorized person couldn't get it off very easily?

Answer 1

Many general merchandise retail stores and parts shops sell these.

Answer 2

Go to your favorite parts store and buy a locking gas cap that fits your car.

Answer 3

Try to find one at an automotive store.  Or go to Toyota and they'll order you a locking cap for about a thousand dollars.  (Well, maybe a little less, but not much less).