Cost estimation of semi-detached house by architects

Hello,
we have commissioned an architect with the preliminary planning of our semi-detached house. (It is only about the costs for the house; the plot is available).
A clear objective is a simple, cost-effective construction method.
The house will not have a basement and the slab will be partly elevated.
(the plot is slightly sloping, but not a hillside plot)
The architect has created a design with 120m² of living space and 19m² of usable space (basement replacement + hobby room). He has calculated 600m³ of enclosed space.
From this, his cost estimate results in 139m² of living and usable space according to DIN
1489€ per m² (cost group 3) or 1714€/m² (total) (or 206,000 / 238,000 €).
Are these values realistic for southern Germany or can a simple construction method also be achieved at lower costs?

Actually, we had hoped that it would be possible to build a small house for 170,000 including all additional costs.

Thank you very much for your help!

Hello jimbo,

per m3 of enclosed space you can estimate between €300 and €400 depending on equipment, heating technology, etc., or about €1300 per m2, so €180-210k plus additional costs should be correct. Basically, the smaller the house, the higher the costs per m2. If I now subtract only €15,000 for the foundation slab with earthworks and €20,000 additional costs, you still have €135,000 left for the house for turnkey according to KfW Standard 70. So you need to plan at least 30 m2, better 40 m2 smaller, then it might work.