At them moment I have one of those "1 week for one page" thingies and it keeps unnerving me.
Anyways... when we started a lot of things were unclear. I had a rough plan of the cats' house but the more pages Lew and I did the more complicated it got.
Where's that cupboard? Where's the desk? If I have bird perspective will it look good. Should I zoom in? I had to do a lot of corrections because while drawing I realized the perspective sucked. Or didn't look right.
We decided to use Sketch Up. Lew was so patient and constructed the house up from scratch (isn't she great?!). We based it on the logic of the first comic pages and ended up with a pretty weird house probably nobody would built like that but it's cozy and I'd totally move in (if the kitchen was bigger...). Having a rough construction helps A LOT. If you ever decide to do something longer with a lot of interaction in one place you might be interested in using the (free) Sketch Up as well.
I still have to draw everything (digitally) and add a lot of details but the base is always correct and we can move the angle till the view looks perfect. It won't safe that much time in the beginning but the more I work with those screenshots the more I love it. Sketch Up doesn't love us back and is buggy as hell but that's bearable.