My house is usually a 20 minute tidying away from photo worthy, out of necessity for me. I can't live with a mess (it causes serious anxiety), but I also don't want to spend my life cleaning or make my family crazy, so the key is editing and having a place for everything.
We keep very, very little on the first floor. Only what is absolutely necessary, so it requires very little upkeep. Just actual cleaning (vacuuming, mopping, dusting, etc and kitchen cleaning), since there really isn't much to pick up.
DS1 is allowed to make as big a mess as he wants with whatever toy or play set he is currently playing with, but it has to be put away when he's done. This does take some effort on my part since he's only 3, but it's worth it to put in the effort to train him now. When I notice him wandering away or going to pull something else out, I just remind him that we put toys away when we're done with them, and that if I have to pick them up I will put them in the trash.
Literally everything in this house has a home. Some closet, cabinet, shelf, drawer, box, basket, etc where it belongs. I LOVE Ikea's Expedit shelves with Target's canvas boxes for toys.
Robbyn, SAHM to Silas, 4/3/09 and Griffin, 3/23/12