You’re relocating to a house with security components
A new home may come with an existing security system. All the devices function well, are installed in the best places, and are ready to go. In this instance, just pick up the phone to call and establish a new monitoring contract. A Vivint installer will still come out to make sure there are no usability issues, and they may offer suggestions on an upgrade or two. It's a fast visit, and you can have your alarm monitoring set up without paying for any new alarms and cameras -- unless you make additions.
The outgoing owners can give an existing Vivint contract to your family for a one-time set-up fee to make the process simpler. If the previous owners are moving to an apartment complex or retirement community, transferring the home security service might be an addendum of the sale.
You want to move and take your old components with you
You might want to bring your old Vivint system with you to a new place when you move. It should be fairly easy to do, as most smart devices are plug and play. You can remove each component by yourself or contact a professional installer to dismantle the system. Then a pro will hang the same devices -- and any smart items you need to add -- in your new house. And your home security contract will keep the same.