I believe that has very little to do with the place of residence. Have you already included things in the offer before signing the contract or do you let yourself be "surprised" during the sampling?
That is true, many people in the eastern federal states have lower, but still completely sufficient, demands. I also know people who want to build a house for under 100k€. Of course, this only works with Eastern European companies (Poland, Romania, etc.) and EL. Whether it all pays off can be seen later. However, much of what is sold under the guise of energy saving and ecology does not pay off in life. And one can ask oneself whether one really needs granite window sills, walk-in showers, ventilation, electric shutters, stainless steel rails, etc., or just simply wants them. I think quite a few people, especially in the German envy society, also do not want to stand behind their neighbor.