How much space do we really need?

When my husband and I were first married we shared a half a house with another couple.  We had a 13 x 17 bedroom and a bathroom to ourselves, but everything else we shared with sometimes two or three other people.  My husband brought boxes of stuff over from Germany, still don't know what all was inside of them, but there were enough of them to build a makeshift wall about 4 feet high.

I brought over whatever I needed for work from my apartment in California, but the rest of my stuff went to my parents basement, their garage, my old room.  There were a handful of outfits that I wore on a regular basis, and I didn't really need heavy winter clothes in Florida, so they got stored, somewhere.  You know,  just in case one day it snowed.

When I got pregnant we moved into a two bedroom apartment and somehow along the way we acquired enough stuff to fill that.  When my son was two we bought a three bedroom house with a two car garage, and filled that too.  The guest room was really just more storage space and after a year or so we couldn't park any of our four cars in the garage that we found a way to fill with more stuff we needed or would need at some point.

When we moved to Germany with our now three kids, we scaled back, to what turned out to be two bedrooms, a living room, a kitchen and dining room.  There are two rooms downstairs, one for storage, and one that is heated and can be used as a guest room.  The garage holds the car, because after 4pm there's no street parking, and it's so tight there's no room for anything else. And the way I drive, it hardly holds the car, itself.  I packed up 73 boxes, only a third of what we owned in Florida, and still I have about a third of that still unpacked in my basement over here.

Sure it gets loud, but I can vacuum my house in under a half hour.  I know when every child is doing something dangerous without having to leave my bed. But everyone still has enough private space, and we don't have to buy a bunch of stuff so that the rooms look like they have a purpose.  At first the kids shared a room and we had our own room.  Then as my son got older he got one of the bedrooms, and the girls share one, and we converted the dining area to our master bedroom by placing cabinets to divide the space.  One of the ideas was to get the toys out of the living area, and to give my son some privacy.  So what happened?  My son makes up excuses to sleep in his sisters room, his room is pretty much just a mess, and the toys make their way into the living area, usually under your bare feet, generally when carrying some hot or fragile.

They like to be together.  When I try to get some space, they come find me.  They have to be touching me or sitting very close to me.  They have to be on the same spot on the couch together and fight over it, even though there's plenty of space on the other end of the couch.

At what point in their lives do humans want to be alone in a 18x24 bedroom with nothing but furniture, trinkets, and electronics?  I mean normal, healthy people, not over-stressed, over-stimulated, over-tired moms of young children.
I finally convinced myself that my old clothes and old toys I that could never before part with would be better off with strangers that needed them then they would be sitting in a box in my basement.  The first thing I sold was the bed in the guest bedroom.  The woman who bought it for me sent me a picture of her daughter's new room featuring my old bed.  I couldn't have been happier.  That bed had a purpose.  It was being loved by a little girl who now had a big girl bed.  And I had one less burden in my life.