Is a bungalow in Walldorf feasible within our budget?

Screenshot!
No idea if this is your residential area.

But: but WA1 - WA4
Only the maximum height applies there?

But: only WA1 - WA4 There only the maximum height applies?

Note (third line) is the Roman 2: II means two-storey

I recorded it again: Plot 20 x 22.5, 5 meters setback at the front, back not considered. With side carports, I end up with a polygonal base plate with 100 sqm living space if I plan a 3-meter-wide light well on the long side. Good grief. Luckily, no simple bungalow is planned. If you let more than an average of 1.40 of the basement protrude, it becomes a two-story. However, with many steps at the entrance and on the terrace. That's not nice either. Do a reset and defrag on your end and start with Plan B. But then with proper specifications.

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We are also not sure yet whether to go for a prefabricated house or a solid construction house. What would you recommend? In the case of a bungalow, there is hardly any structural engineering to consider. Wouldn't it be cheaper to do without a prefabricated house company?

One does not exclude the other. There are also prefabricated houses made with solid construction.

Structural engineering is always important and independent of all types (prefabricated, solid or wood, standard house or architect). It is always calculated and must be comprehensible for the approval.

Note (third line) is the Roman 2: II means two stories

But I read it as you can have 2 stories, but don’t have to. Regardless, it’s not bungalow territory. Too small for that.