Designing hillside property - Earthworks / Retaining wall cost options

It wasn’t about floor plan discussions of the house, but about the layout of the outdoor facilities (which may possibly influence the position of the house) – so I want to consider everything as a whole from the very beginning.

So what is it now: consider everything as a whole or not? – for that purpose, although it doesn’t require (and is even better this way) a fully elaborated floor plan, it does require its concept already. Abstract partial considerations are not holistic! Many home builders here (especially forum newbies) make the mistake of “building upon” initial basic considerations here; but to call that “as a whole” is new :) By the way: 9 x 10 m floor area results in just under 110 sqm living space in the “one-and-a-half-story” and with a basement roughly reaches the desired 140 sqm.

The written development plan can be found by googling

Exactly, Möckmühl Brandhölzle 3rd development phase ... WITHOUT link! Meanwhile, I have also dug up a reading tip for you: check out – he has a similar slope and development plan, but situated about two hundred meters lower in elevation, and the parking space solution is more cleverly arranged.

Crazy, actually only the name was supposed to be copied & pasted for googling and then it was automatically linked .. unfortunately I can't edit my post apparently.

A floor plan is of course also planned, I was mainly interested in the design of the height differences of the property and the cost of retaining walls. As written, there will be 2 full floors of 9x10m with a 2.4m knee wall. That makes 140m2 without a basement. Current floor plan planning attached for basement and ground floor ("still somewhat in progress").
Basement:


Ground floor:

Meanwhile, I have also dug out a reading tip for you:

So then, in the meantime I have also read in the justification (from page 16): Deviations from the fixed ground floor floor heights are allowed to a certain extent (max. 0.5 m) upwards and downwards in order to provide the builder with sufficient scope in the design of the entrance and ground floor situation. [...] In the case of the construction of a building on two defined ground floor floor heights, an average of the two values is taken. This way, the buildings integrate into the course of the street space. Exceptionally, both ground floor floor heights may be applied, for example in semi-detached houses that are based on two ground floor floor heights. On the one hand, I see quite a considerable range of possible heights in this, and on the other hand, even the possibility is opened up to build split-level.

A different question? How is the budget? Already tight or doesn't matter?

I see potential savings with the driveway, the [QM], and the placement

For your outdoor area from the 1st post with driveway, retaining walls, earthworks, drainage, planting, terrace, you will be heading towards 100 k in pure subcontracting.

Yes, exactly, so from the 4m height difference from west to east. The detached house is located pretty much in the middle. In my representation, the 0.5m is already included. We want to build as high as possible. On one hand, because then we have a better view of the valley, on the other hand, because less earth has to be removed.
Split level will not work though. a) we don’t need an exit towards the west and b) that would mean a lot of earth removal with high costs c) with the exit we would even be below street level.

The budget is already rather tight. In total we have 750k. The plot is already paid for.
I calculate:

House 140sqm with basement: 500k
Additional construction costs: 80k
Carport + terrace roof: 30k
Outdoor facilities (paving, retaining walls, hedges etc.): 50k
Solar system: 25k
Controlled residential ventilation: 12k
Kitchen: 25k
Lamps/furniture/etc.: 10k
Buffer: approx. 20k

100k for the outdoor facilities would already be quite a lot... are there variants (also with different house positioning as you mentioned) that would be cheaper?

Can you explain the savings more precisely?
Smaller than 140sqm will be rather difficult. We want to have 40sqm pure cooking/living/dining area.
Since family often comes to visit, about 12sqm are also planned for the guest room.
The size of the 2 children’s rooms is also important to us with about 16sqm.
Representing that in less than 140sqm is a bit difficult. Of course, the basement with 2 living rooms facing west (including underfloor heating) is a small luxury for a hobby room / 2nd office.

How could money be saved on the driveway? In the end, it has to be quite wide so that a car can be parked next to the entrance and at the same time with the entrance platform there is still enough space.