My brother is like this. He's married with kids now, but I went to visit him when he was single and boy was I shocked. I was expecting a typical bachelor's pad, but instead I walked into a spotless apartment with two chairs at the kitchen bar and a bed in the bedroom. There was nothing on the counter tops. He felt that furniture was just too much clutter for him.
Now his wife complain that he freaks out when she moves things in the house. Everything has a place and must be positioned just so. He's ok with the kids' stuff being all over the place- it's just the stuff he needs or uses has to be exactly where he puts it. He thought it was OCD, but the doc said no, just a coping mechanism for ADHD.
Ever since my dd was a tot, she would ask for the clear plastic baggies IMy daughter used to have a very messy room. Finally put my foot down and said she'd have to clean it, or I would. And if I cleaned it things were going in the trash. She refused, of course, so I cleaned. I took EVERYTHING out of there. Hehehehe. She was left with a bed, a dresser and a lamp.
Oddly enough she loved it. 
Hehehe.
Since then she has kept her room very clean. On occasion it gets a bit messy but she will clean it up - the less she has in the room, the happier she is.
How interesting! My DD is a 'Bag Lady' too! Hehehe. She loves bags. It does help me keep her organized - the red bag for Highland dance, the pink bag for ballet the striped bag for piano, the plaid bag for school, etc. I can imagine how many she will have as an adult once I am not there to put the brakes on her bag buying.
alisonsmom39525.517962963My 9 yr old son keeps his room very organized. Everything has its place. He