I am redoing all of my 4 smoke detectors in my house and I like to add more to other areas.
The current ones are FIREX using AC (not battery operating) all linked together through the red wire (14/3 wire, black: Hot, white:netual, Red:connects all the 4 smoke detectors).

Here is the location of the current 4 I have: (4 levels: basement, 1st floor, 2nd floor, attic)
1 in the basement, next to the stair case going up
1 in the 1st floor, next to the stair case going up
1 in the 2nd floor, a few feet away from the bathroom
1 in the walk-up attic

I believe all 4 are ionization type.

I like to replace them all with the appropriate smoke detectors type, and also
Add one to the 4 bedrooms on the 2nd floor.

Questions:
1. There are ionization type (radioactive type), and photo electric type, also ones
With both (which people claim has false alarm alot), as well as one with monoxide
Detector. Kiddie brand seems have lot's of options. Which one should go to which
Room? More specific details, below.

2. I partitioned the basement into basement play room, and a separate utility room
Where oil-tanks, heating system, water tanks, circuit breaker lives. What type should
I put in the basement, and what type in utility room?

3. what type on the 1st floor. I have a kitchen that's 10-15 feet away from it.

4. what type on the 2nd floor, where is only a few feet from the bathroom,
Which has steam in the area from taking showers.

5. Since attic gets either super hot or super cold (it's unfinished), what type
Should I put in the attic.

6. Finally, with bedroom doors closed at night until morning, what type
Should I put in the bedrooms? Each Bedroom typically has a bed with a mattress.
Wood desk, clothes, etc.

Thanks in advance

Besides each floor, 1 in each bed room, AND outside of each bedroom. 1 in hall may be used if doors are next to each other.
Most Big Construction stores have 120 volt with battery backup and interconnected. A heat detector may be better in Kitchen.
They also make wirekess interconnected smokes that are handy if wiring is impossible or unsightly.

Thanks for your response.
Any idea on which smoke detector sensor's type is good for the rooms I listed in my post?
Thanks again,