Floor plan of a single-family house approximately 150-160 sqm on a 480 sqm plot in Middle Franconia

Here is the template based on the information from the OP.

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Exterior wall is measured at 35 cm?

Short side according to manufacturer outside 8.20 m

For that with a basement, which will almost certainly exceed the 550k budget...

But with a basement, which will pretty much certainly exceed the 550k budget...

The house provider foresees an extension there. But not for free either.

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is there a development plan? Where are the parking spaces supposed to go?

According to BYA, the plot is about 21 m wide. Where do you get the 18.5 m from? Slope to the north 1 m, slight incline.

The house provider envisions an extension there. But not for free either. [ATTACH alt="Grundriss109.JPG"]70402[/ATTACH] is there a development plan? Where are the parking spaces supposed to go?

House provider or not, the thread starter wants to put the HAR, an office, and a guest room in the basement...

Whether you use a house provider or not, the thread starter wants to put the HAR, an office, and a guest room in the basement...

I would not provide a basement, especially not with that budget.

There is a parking space regulation from the municipality. What does it say?