3.Bullet Resistant Doors
Making it into the top 3 most expensive security systems billionaires use are the Bullet Resistant Doors.
Price: $400.000
One of the costliest, but most popular billionaire home security item is a bullet resistant door, that can cost up to $400.000 per piece.
The doors are fitted with electromagnetic locks that don’t allow anyone to access the room or the house, without a proper authorization. If someone fires towards the door, it has the capacity of shielding the bullet.