Something that makes the garage at Oberon Wood more interesting to model is that it is built into a slope.
In order to be able to mount the model on a flat surface you are obliged to build it like the proverbial iceberg with a certain amount of the structure hidden beneath the surface.
It is complicated further in this case by the rendered walls following the contours of the land around the building with a foot (30cm) or so of brickwork exposed at its lower edge.
My solution to this has been to make the building in two distinct sections.
The upper part, with the rendered walls which slope at the sides and is taller at the front than the rear, was made up from four sections of 0.60" styrene.
Then a second box, which sits flat / square at the bottom was built up inside.
The picture probably explains this better than words.
What I will do next is fix brick embossed styrene sheet to this lower section. This sheet is about half the thickness of the 0.60" which I made the top section from so I will still get the effect of that lip between the render and the brickwork.