How to prove that the developer or property has handed over all the keys to the entrance door and th

There are two sets of anti-theft door keys, one of which is a decoration key, generally two. Second, the main key, the main key is wrapped in plastic, as long as the two sets of keys are handed over to you, it means that there is no key to your house. As for the problem of invalidating the decoration key after inserting it, it is very simple, in fact, the decoration key and the main key you compare with their bullet holes, and you will understand.

There is a pinhole with a different depth, and when the main key is inserted, one of the pins in the cylinder will jump up, it's as simple as that. I don't know if I understand?

Now it is usually equipped with an installation key, and when the door is installed, you just plug it in with your own key and it won't be able to open. If you still don't feel at ease, you can change the lock cylinder yourself! The money is not very expensive,,It's just 10 yuan.。。

Your question is obviously illogical. Your question is equivalent to: how to prove that the developer and the property do not have your house keys in their hands. Let a person prove that he has nothing to offer? It's impossible. Illogical!