You’re buying a house with home security components
A new house may come with an existing security system. All the alarms and cameras function well, are placed in the best spaces, and are ready to go. In this instance, just get the phone to call and establish a new contract. A Vivint installer will still show up to make sure there are no usability issues, and they could offer suggestions on where you should replace bad outdated components. It's a fast trip, and you can have your 24/7 monitoring set up without having a bill for any new alarms and cameras -- unless you get some new devices.
The outgoing owners can transfer an existing Vivint contract to your family for a nominal set-up fee to make your life simpler. If the outgoing residents are moving to an apartment complex or smaller home, you keeping the Vivint service may be a condition of the sale.
You are looking to move and bring your existing equipment with you
You might want to bring your existing home security components with you to your new place when you move. Luckily, it's fairly easy to accomplish, as many components are plug and play. You can take down each device yourself or use a professional expert to dismantle the system. Then a pro will hang the same components -- and any smart devices you need to add -- in your new house. And your home security contract will remain the same.