Terrace on a hillside on stilts - wood or steel better?

The neighbor's information is still new, so I could only send a text message to my architect, and we both just came back from vacation today. Honestly, the whole thing annoys me. If we had started without talking to each other (i.e., the neighbor), we would have a problem now because the L-bricks towards the southern neighbor would have been too low, and the southern neighbor would have only allowed 1m after consultation.

I would imagine something like that, just without the side staircase. I have no idea what something like that costs.

Something like that would be my idea

That's how I had already understood it, and I meant: it would probably make the most sense to design it together with the carport (and to construct it using the same materials).

I have no idea what something like that costs.

I said (from about four years old memory, what a former employer of mine would have charged for it in aluminum) that at today's rates it would be 40k EUR or a bit more.

Then I’ll try to construct it. Additional costs:
- Excavation including landfill: 13.5k€
- Construction including carport: 40k€
- Exterior plaster for cellar: 8k€
Total: 61.5k€
Minus 26k€ L-bricks (removed)
Minus 12k€ carport (original)
Minus 20k€ exterior landscaping (original)

Seeing it this way, I would still be missing about 10k€ for the fence and paving the driveway or the remaining paths, right?

Can I actually have the original perimeter insulation (cellar) plastered or do I need something else for that?

For a steel construction made of galvanized HEA, I would estimate about 7,500 euros. I assumed 45 meters of HEA100 beams for this. Pure material costs about 2,500 euros, the rest goes towards structural engineering, assembly, delivery, and corrosion protection. Then there are the shed or carport and the foundation work added on.

I wouldn’t build something like this out of wood; the maintenance effort would be too high for me.

For a steel construction made of galvanized HEA, I would estimate about 7,500 euros. I assumed 45 meters of HEA100 beams for this. Pure material costs about 2,500 euros, the rest goes for statics, assembly, delivery, and corrosion protection. Then come the shed or carport and the foundation work on top of that.

I would not build something like this out of wood; the maintenance effort would be too high for me.

Thank you for your assessment. I also believe that we will not consider the wooden option further.

I just had a phone call with my architect. At least we agree that this kind of terrace construction is the most sensible way now, and we will not install more and higher L-shaped stones. However, he thinks that the carport and the tool room should not be included in the terrace construction, as that would simply become too expensive. In my opinion, this construction will be the cheapest (like above but without stairs). The carport will then have to be partially supported with 2.5m L-shaped stones. How long that will be still needs to be clarified. See the screenshot. 3m should be enough for a garden table (widthwise) with chairs.

I have an appointment with the metalworker on 12.6. and will gauge what this idea will cost.