Many homes change hands with an alarm system already on the walls: a keypad by the door, contacts on the windows, perhaps a motion detector in the hallway. That equipment can be a head start, but when you move in you do not know who still has codes, whether the system works or who it reports to. Before you rely on it, take a few steps to make it yours.
Start by identifying the equipment. The control panel is often in a closet, utility room or garage, separate from the keypad. Look for a brand name on the panel, keypad and sensors, and photograph any labels. If the previous owners left manuals, account information or a sticker from an alarm company, keep them.
Then ask the sellers or their agent what they know: which company monitored the system, whether the monitoring agreement has ended, what the master code is, and whether any equipment was leased rather than owned.
Previous owners, their family, cleaners, contractors and anyone else who was ever given a code may still know how to disarm the system. Treat every existing code as compromised. Changing the codes, including the master code that controls the others, should be one of the first things you do. If you cannot change a code yourself, or the panel has a separate installer code that the previous company still controls, that is a job for an alarm company.
A keypad that beeps and arms does not mean anyone is watching. The previous owner's monitoring account may have been cancelled when they moved, or it may still be active under their name, which could mean alarm signals go to people who no longer live there. Neither is what you want.
If the system is still connected to a monitoring company, contact them. Tell them you are the new owner and ask what it would take to transfer, restart or cancel service. If you plan to use a different company, ask whether your equipment can be taken over or whether some of it is locked to the original provider.
Do not assume every sensor works. Batteries in wireless sensors may be old, contacts may have shifted, and a detector may have been painted over while the house was being prepared for sale. Ask a technician to test the system. If you are confident with the panel, put the account in test mode with the monitoring company's knowledge first, then open doors and windows one by one to confirm each is reported correctly.
The previous owner's system was designed around their life, not yours. Walk the house and note which doors and windows are protected and which are not. Perhaps a back door was added during a remodel and never got a contact, or the garage entry was skipped. Think about your own routine too: whether you have pets, whether anyone works from home and which entry you will use most.
Once you know what you have, there are three realistic paths. You can keep the existing equipment, change the codes and connect it to monitoring. You can keep what works and add sensors where there are gaps. Or you can replace the system if it is old, incomplete or locked to a provider you do not want.
A local alarm company can help you weigh those options. Kingwood Alarm, for one, puts a consultation and a plan of services near the start of its process, and that meeting is a good moment to bring your photos, the panel's brand name and the list of gaps you found. Its stated aim of charging only for what a property needs matters here, since part of the existing system may be worth keeping.
Whoever monitors the system, make sure the account is in your name, with your current phone numbers and a contact list of people near the new home. Set a verbal passcode that only your household knows. Check whether your city or county requires alarm registration or a permit, and whether anything held by the previous owner needs to be updated in your name.
Alongside changing the locks, add the alarm to your move-in list: new codes, confirmed monitoring, tested sensors and an updated contact list. It takes a little effort in the first weeks, and it means the system on your wall is working for you rather than for whoever lived there before.
Keep a simple record as you go: the panel brand, which zone is which door or window, who your monitoring company is and how to reach them. The next time something beeps, or the next time you sell the house yourself, that record will save a lot of guesswork.