To be fair, our house renovation was done by a gang of "gypsy" builders over nearly 5 months of the first Pandemic Summer. It was a lot of work! I dread to think what that would have cost me in the UK.
Here's the before. You should note the plastic over the downstairs (= ground floor and basement) windows, and big empty space below the lounge (the main reason why upstairs was impossible to keep warm in winter, with the cold wind sucking the heat out). It doesn't look very big, but it's rather awkwardly divided into 3 zones (below lounge, ground floor below bedrooms, basement) on 3 slightly different levels, which add up to nearly 150 m2. Each zone needed new floors and new stairs to get between them.
https://photos.app.goo.gl/qd9jc3Xai3CdMhf79
This is the after, with new walls below the lounge, new terrace in front, new porch on the side. New UPVC windows in the ground and basement floors, new doors to the porch and basement, everything with external insulation and render.
https://photos.app.goo.gl/xg3MAk6Ghp717ztb9