ᐅ Semi-detached house 7x12 m with additional rooms on the ground floor

Hello everyone,
we have been offered a plot of land measuring 10x60m (33x197 ft) for a semi-detached house. The other half will be built by friends of ours who have similar requirements.
Now we are considering how this could fit our needs.

• The house dimensions are specified as 7x12m (23x39 ft) or 6x10m (20x33 ft), with two full stories and a gable roof. The plot is flat, and the terrace faces south-southeast.
• There are five of us, and we need three children’s bedrooms, one master bedroom, an open plan kitchen-living area (preferably with a kitchenette tucked into a niche), a bathroom, a separate toilet with a shower, a utility room (with solar storage and heating system), and a cloakroom.
• The three children’s rooms and the bathroom should be located on the upper floor.

We are now looking for a floor plan that includes space for a bedroom on the ground floor—12sqm (130 sq ft) should be sufficient. If possible, I would then place the utility room under the roof. The rest of the attic space would be used for storage.

So far, I haven’t been able to find any floor plans online that include an additional room on the ground floor.
Do you have any pictures or links for me?

At some point, the children will likely move out, and we will need less space. It would be nice if it were possible to separate a self-contained apartment. This should probably be considered now so that the later effort is not too great...

I look forward to many ideas and pictures.

Best regards,
Simon