sawz that is a good unit, kind of the go to unit for most contractors, congrats on going through the trouble and making your family more safe... I feel very strongly about fire safety, a few bucks, a little time and some attention to detail and you can save your family, seems like a no brainer to me...
I have one of these in each upstairs room of my house $30 each seems pretty cheap to me
My home fire alarm system is pretty thorough, heat sensors in the garage and over the heating systems, smoke/cos hardwired throughout the house including in the attic and inside the duct work trunk lines {36 in total} hardwire powered with internal and external battery backup, monitored through my security system, plus a gas/co/smoke detector wired to shut my boilers down, ect ect ect and it all cost me under $4000 when i built the house!!! that's a small price to pay for something that can save your families lives... The monitored system is tough, because you don't want your firedept showing up every time the kids burn toast, BUT I have a 3 minute delay and all I have to do for it not to call the alarm service is hit one of the 8 silent buttons or a button on any detector {but my ceilings prohibit that from happening, unless I go get a ladder or broom and by then the fire dept will be there lol}... Another nice option with my system is after hour alert, if my smokes get alerted after 10pm and before 7am my house alarm sounds, the hallway, stairway, and outside lights all come on, and you are not sleeping through that...
But anyway, even a cheaper system, fire extinguisher on each floor and in kitchen, ladder in each upstairs room, smoke/co's in every staircase and hallway you can spend under $200 and be much safer... Also the even the best system in the world can be worthless with out a plan, I go over it with my kids a couple times a year, let them use their bedroom ladders, check everything out, change batteries, ect... If the alarm goes off, they know, check their bedroom door, check for smoke, look into the hallway {the emergency lights will be on if the alarms are sounding at night}, if there is smoke they go out the window, if they can get to one bedroom I prefer they both go out one so they can help each other, then after outside they know our meeting spot, and they are to wait never go back in... I have fire drilled them and they seem to be prepared, they can get out of the house and down the ladder in under 120 seconds, now in an emergency where they see smoke and don't see me, I don't know but at least they will know what to do... I have my own plan too for me and my wife, my bedroom is at the end of the hall, so in case of a fire I am going to my sons room which is at the end of the hall on the other side of the house making sure my other son and wife are with me and we all go down his ladder...
Hopefully we never need this stuff, but the house I grew up in burnt to the ground when I was 14, we lost our dog, cat, and house... My parents rebuilt on the same foundation but we had a fire plan and drills after that....