Transition from brown house with one window to red building with many windows

[whewfan]

The first episode with the brown walls was the debut of the brown house with one window. Shortly after, orange shutters were added to the window.

Here's where it gets strange... at some point, the brown house gets repainted red, and the one window remains, but no shutters, but it alternates to the red building with many windows. In fact, there were a couple episodes that started with the one window red house, but the ENDING CREDITS featured the red building with many windows.

What happened here? Did they decide to paint the building red, then put the window on, and realized it just looked awkward? It was only on for a few shows. Then the building with many windows was introduced and stayed until the final season, where a fully modified model of the neighborhood stayed for the rest of the run. (In the final season, the red building's windows look more symmetrical and no look like paper cutouts. Brockett's bakery, Joe Negri's music store, and Betty's Little Theatre get upgraded too similarly, with plastic windows instead of paper. Bob Trow's workshop is now a pink house with one second story window and Fred's house is now yellow and is on the adjacent corner, rather than the last house on the left. The yellow house looks more like the layout of Fred's house on the inside.