You’re buying a place with home security components
A new home may come with an existing home security system. All the alarms and cameras function well, are installed in the best areas, and are ready to go. In this instance, just turn on the phone to call and set up a new contract. A Vivint professional will still show up to make sure there are no usability problems, and they might offer ideas on upgrades. It's a fast visit, and you can have your alarm monitoring set up without paying for any new devices -- unless you add on.
The outgoing homeowners can transfer an existing Vivint contract to you for a one-time set-up cost to make your life a snap. If the previous owners are moving to an apartment complex or retirement community, transferring the security service may be an addendum of the sale.
You need to move and bring your existing components with you
You may want to take your old home security components with you to your new place when you move. That’s fairly easy to accomplish, as modern alarms and smart devices are wireless. You can uninstall each device yourself or use a Vivint installer to come and take down everything. Then a pro will put in the same components -- and any smart services you want to add -- in the new home. And your home security contract will stay the same.