If you are not a professional, the last thing you want to do is to mess with your gas piping. This is a serious mistake. With a water leak, you get damage. With a gas leak, you die. If you are not licensed to work on this. Do not touch it. Your cost savings is not worth your families safety.
The questions you have asked, tell me your level of experience with Methane (natural) gas.
I say this, as a master plumber, college teacher, and OSHA trainer.