Below is going to be made law in Scotland, I already have alarms so they
can fekc off!
However thinking of some old dear on a state pension or someone on
benefits what would be an approx cost to get an electrician to fit as below.

Quote............
"Now everyone will benefit from the same level of protection, whether
you own your home, or rent from a social or private landlord."

In practical terms, the law will require private homes to;
have at least one smoke alarm installed in the room most frequently used
have at least one smoke alarm in spaces such as hallways and landings
have at least one heat alarm in every kitchen
have a carbon monoxide detector

In addition, there will be a 10-year age limit for alarms and all alarms
will have to be ceiling-mounted, and should be interlinked.".........