European homes tend to be much smaller than American homes and are very rarely stand alone single family homes. I get to the UK often and almost everything is connected and have small little “gardens”. This is fine and it makes for cheaper construction since there are far less materials and labor is shared across many homes. The hones are tiny by American standards too.
We don’t have this as much in the USA. People generally want single family homes that are 2000 square feet+ and 1/5 acre of land. This is a lot of roof, a lot of siding, a lot of timber, a lot of flooring, a foundation, etc. Easily 6-figures in materials and even more for labor, etc. Especially if you go with premium materials. Windows installed are $2k/window. My would cost $70k to install all new, premium windows for example.
Premium hardwood quarter-sawn flooring in a 3000 sq foot gone is another $30k, etc. You can start to see how this adds up from $100k+ in materials for trash to many hundred thousand for premium, quality materials.