Just for the record, I don't go into my kids rooms unannounced and clean them. I give all of the kids a couple weeks notice, and give them the chance to clean their rooms themselves.
They are given a couple weeks to get the rooms clean, and I remind them daily to clean it or I will do it for them. Once "D-Day" comes around, if the rooms aren't clean I do it.
I don't just throw away their stuff. If it is garbage, broken, too small or too young for them (toys and books), it goes into the garbage or to the Good Will.
#2 and #3 don't mind me doing this. #1 voices protests, but when he doesn't clean his room and I do it, he thanks me profusely.
If they have treasures that are special to them, it gets placed in an appropriate location. If it is a toy that I have not seen them look at or play with in over a year, it goes out.