Because of the ridiculous planning and land laws in the UK a handful of major builders most of the homes. They may give you a choice of the front door colour and kitchen units and that is about it. An artificial land shortage ratchets up land prices and the knock on is small pokey, poor built homes. Modern homes, since WW2 are pitiful.
I like this... an eco German kit house - Huf Haus. They erect them in the UK
Bolted together with stainless bolts to German precision. Heating bills are pennies.