Bought the house in January 1999, moved in February 1999. Slowly but surely, getting it done.
Room number 4 with sanded and refinished fir floors.
Pretty much got it down to a science (albeit a very slow one more akin to evolution than space flight). Sand the floor with 40 grit belts on my 18" belt sander. Re-sand with 80 grit belts, then with 120 grit. Apply sealant with an applicator pad. Let dry two to four hours, apply Bona Mega polyurethane floor coating. Wait a couple hours or so, sand lightly with a 220 grit sanding pad (Bona says this is not necessary but I do it anyway to catch any lumps in the coating) and vacuum then damp mop, apply the second coat, repeat as needed. I did three coats on the bedroom floors and five on the most recent front hallway since it is high traffic. (Yes, I went there. My bedroom is not high traffic).
Coming up, you can see the front porch in the foreground of the picture. Unfortunately that one will have to be torn out rather than sanded and refinished since a foot along the outside edge of the enclosed porch was cut out (presumably rotted) years ago and replaced with plywood.
Either way, coming along nicely, except for the fact that I only have one floor left to refinish and then I will have to learn a brand new skill like laying tile or replacing a whole floor. Oh, and the house needs to be jacked up in a couple places, but how difficult could that be?