Enough to not want to kill the others with whom you live!!!  Your layout would land me in jail

We do not need as many rooms as we have. 

It is all relative... I have seen homes with a Family room, Living room, Great room, Den, Library and so on, all in one home! Too much.

For what?

I only NEED a kitchen, bathroom and a bedroom but I WANT a Family room, gym, sauna, extra bedrooms, finished basement and maybe a heated indoor pool.

For my wife and I that would be a total of 8.

We've downsized and really like our smaller home.  

Not as many as I once thought neccessary! Downsizing is great!

 Good Wednesday morning Jack. It was amazing how folks lived in one room cabin. Today, we need a room for everything.

I just downsized and I like this way. I do not want empty rooms in my house. Ideally I'd like to have a theater, a gym, a ball room,  a sauna, and indoor pool~ but I do not have them and I'm fine with that.

You forgot a closet. Instead of a walk-in closet, I would like an entire bedroom to be turned into a closet. 

I am content with one at a time, if not for the rest of my family I could survive with an efficiency apartment

As far as needs then the same as you, but wants would be an office, gym, library, meditation room, bathroom, bedroom, kitchen, living room, and dinning room. 

I don't need many. I downsized about two years ago, and I love it. 

In my house there needs to be more than 3.  We definately need a greatroom. We spend lots of time there.  And frankly  I have to have a second bathroom in m house.  I don't share well. 

Living room, Kitchen, 2.5 Bathrooms, Bedroom, Guest bedroom, craft/exercise room. = 7.5 rooms.

I would go for 4 - I love my family room with its fireplace. 

Well, I raised 5 kids, so I needed rooms. 

I only need 3, a bedroom, a bathroom and the kitchen.

Four for me.  A bedroom, bathroom, kitchen and office.

You ask what I need, not want. I'll say four. Your 3 plus a room for office/exercise/guests.

Jack - Well if you have kids, you will want one room for adults (to relax, watch TV, or entertain), and another room for the kids to play in and enjoy. So at least two more rooms for me, as well as 1 bedroom for each child to sleep in. Also, would like a laundry room in my home, and probably at least one additional bathroom (other than the one in the master bedroom). Don't need a formal dining room, but do need a place to eat, which can be in the kitchen. It would also be nice, but not necessary, to have a den for a home office.

That's all.

As many as I need!  

For 90% of the year, all my husband and I need is our kitchen to cook, family room to lounge, bedroom to sleep, office to work, garage for him to tinker, back porch to hang with the animals, and a bathroom. The rest of the house never gets used. The other 10% of the year (when family visits) we could have a 10,000 sq. ft house and still not have enough room.

I am used to more than I need but I could live in one big open loft quite easily. 1200-1800 sq ft works.

Ilived in a 700SF 3 room apartment in Houston when I went through cancer treatment and I was amazed at how I liked it. 

I could live in a one room cabin in the north woods

Jack I understand your reasoning, but frankly I would need more room :)

All I can get Jack.