Am sure this has been done before, but it is still useful and potentially life saving
We arranged a visit from our local fire service to advise us on how many smoke alarms we needed in our house plus escape routes etc
We had 3 smoke alarms fitted for free, and had plenty of advice which i hope i will never have to use, but was so useful
I am in Essex and am happy to give the number out, but am sure lots of other counties do it