Modern Family is a hit or miss show, usually with one plot (Cam and Mitchell's most often) which doesn't work well. "Door to Door" has some great moments, but also more misses than usual. The three parties--Manny and Jay, Gloria and Cam, and Claire--end up canvassing the neighbor, and the sequence of cuts is very funny. This point, tying together three threads, was pretty clever and took me by surprise. Manny boosting Jay's ego to get the sale also took me by surprise and I liked how that played out.
Unfortunately, the other plots didn't have as much creativity. Cam and Mitchell have their usual freak out plot where they start screaming and tossing things around, though the adoption agency person coming through the door at the end was a great twist. Gloria finding Stella felt like something the writers tossed in either to fill in time or so Sofia Vergara got something to do.