In Australia, smoke alarms are now inexpensive consumer items. National hardware chains have reduced prices dramatically.
Basic portable photoelectric smoke alarms are available for $12-$15 each. (including a 9v replaceable battery). Most homeowners will conduct DIY installations of portable smoke alarms. Trade attendance rates vary. e.g. $75-$85 for a handyman to attend, plus cost of smoke alarms.
Mains powered (hard-wired) photoelectric smoke alarms are available for $20-$35 each. (including a 9v replaceable battery).
Mains powered smoke alarms need installation by a Grade A Electrician. Homeowners should request a Certificate of Electrical Safety (CES). Typical CES fees are $15-25.
Grade A Electricians charge an upfront attendance fee of $85-95.
Grade A Electrician pricing is then charged on basis of time taken. (e.g. $80-90 per hour) and extra for materials (wiring/cable fittings). This labour rate is often broken down into 30 minute and 15 minutes blocks.
Expect all Trades to double the smoke alarm (RRP) pricing stated above.
NB… Homes built after 1Aug1997 must have mains powered smoke alarms in Victoria, Australia.
The Smoke Alarm Guy