Modular Terrace Kit MTK2 Grimy Brick Terraced Back Yard Cobbles
The Back Yard allows a bit of variation to the cottages, since you can 'slide' it into the back of the cottages to give yards of different length, and also turn it through 180 degrees to give different openings of the gates. You'll need the Back Yard Wall to complete: two for the first pair of cottages, and one for every added thereafter
The screenshot shows a section of completed unit with the components lined up behind. The TBYC is on the extreme rear right, alongside a back yard wall as mentioned above.