Is a descaling system tax-deductible after house construction?

But not if the system was installed immediately upon completion?

Yes, it is possible. I spoke with my tax advisor some time ago. Everything done after moving in can be claimed on taxes. Of course, not the materials and only up to a certain limit.

Just a quick info: I could easily deduct the labor costs!

Yes, you can, if
1. The house is fully built - it is.
2. There are no remaining works - there are.
3. You are not already claiming wage costs above the maximum limit from other craftsmen's invoices. - this is unclear with the information available.

Yes, you can, if 1. The house is completely built - it is. 2. There are no remaining works - there are not. 3. You are not already claiming labor costs from other craftsmen invoices over the maximum limit. - this is unclear given the information.

I disagree ^^ depends on the tax office. In the West they usually approve it like that... with us it was still under construction and billed separately from the contract. It worked out especially since you don't have to submit receipts anymore it can sometimes work.

If the house is still under construction, the regulation does not apply (see point 1). Making an illegitimate claim knowingly without proof – regardless of whether it succeeded – does not please me.

If the house is still under construction, the regulation does not apply (see point 1). Claiming an unauthorized entitlement knowingly without proof - regardless of whether it worked - I do not like.

Sometimes you make mistakes.... you know There are the big fish and the small ones