You moved into a place with a pre-existing home security system
Sometimes when you purchase a home, a security system is already installed. All the components function well, are installed in the best spaces, and are ready to go. In this example, you might find that you have to call and start a new monitoring contract. A Vivint installer will still come out to ensure there are no integration problems, and they might offer options on where you should replace bad outdated components. It's a fast trip, and you can get your monitoring set up without having a bill for any new components -- unless you add on.
The old homeowners can move an existing Vivint contract to you for a small transfer fee to make the process easier. If the owners are moving to a condo or smaller home, transferring the security contract may be a condition of the sale.
You want to move and take your old equipment with you
You may want to bring along your existing Vivint system with you to your new house when you move. Luckily, it's fairly easy to transfer, as modern smart devices are plug and play. You can remove each component yourself or call a Vivint expert to take down the system. Then an expert will hang the same components -- and any additions you need to make -- in the new home. Your home security contract will stay the same.