I've just finished a Steck custom I've been working on for a few weeks so I thought I'd show some photos of that and of one I made some years ago.
First, the new one. It's a one and a half storey design and it's this, plus the lack of a couple of blank walls, that required the custom work. So here are the first four photos, front, side view, barn end view, and then a view with the barn roof off to show the custom wall and the timber work and drainage pieces which help position and support the barn roof. The drainage pieces also disguise the gap between the barn roof and the house end wall. There are close ups of the drainage arrangements later.
The custom walls are made using the large Steck open frame piece and fitting a piece of plastic sheet in it and then sticking strips of painted plastic to the outside of this to represent the wooden framework of the house.
Edited so photos in better order and more detail more custom work.