It's important to note that anything too big for a vacuum cleaner to pick up off of carpet can, with a moment's practice, be picked up with a broom and a dust pan. Don't try to separate everything into boxes and trashcans by hand. It takes too long and it's hard on your back.

Importantly, if trash is a bulk operation, then the cost difference between keeping things versus throwing them out becomes more pronounced, earlier on.

I'm sure most of us have that experience of figuring out that our stuff isn't going to fit in the truck and/or car and all of a sudden things we really intended to keep become negotiable. Problem is that there are probably three other things you'd be more willing to part with, but they're already in boxes in the truck.