Battery-powered smoke alarms cost between £50 and £120 installed, while mains-powered or interlinked fire alarms typically cost £150 to £275 on average.

An HMO interlinked fire alarm system usually costs between £170 and £450, depending on the size of the property and wiring complexity.

Small commercial properties such as shops and offices typically pay £1,500 to £3,500, while larger buildings and warehouses can cost £5,000 to £10,000 or more.

Standard homes generally only require domestic smoke or heat alarms, but HMOs and rental properties must meet BS 5839-6 Grade D or higher to comply with UK fire safety regulations.

Commercial premises usually pay £40 to £60 per month for professional 24/7 fire alarm monitoring, whereas many domestic smart alarms include free app-based monitoring.