This is our recent project. The Dollhouse. It took only an hour to put it together. It's portable. It's cat proof (can be closed and put away). It does not take a lot of space, and is easy to clean up: all pieces stay inside the suitcase when the playtime is over.
We used a Calico Critters Deluxe Kitchen Set.
Take some construction paper, scrapbook paper or contact paper, trace the templates, cut out carefully. Affix the "flooring" first, using double sided tape or glue. Open and close the suitcase a few time to create the crease.
I used the Contact cork for the floor. The result is nice and cork is more resistant to scratches, but it will be more difficult to remove, should I ever change my mind.
Glue the "wallpaper". I used a sheet of scrapbooking paper. I glued it on with the regular school glue.
I think I'll make a "window" to put above the sink/counter. To do this, you can either buy a Dollhouse window or just make a pair of curtains and a small picture (aka "the view"), and glue this onto the wall.
The only thing left now it to invite some toys over for a house warming party. Enjoy!