So you will save 20% of that - maybe CHF1000 refund? I'd just go with it and claim it and see what happens and view it as a bonus if you get it

Dunno what the actual rates were - CHF500 is a bit overstated I think - CHF375 maybe? Ours was a bit complex and we got a tax lawyer rather than an accountant to do it. (It was because we own the shell of the building today but the people we bought it from are also doing the renovation and we needed to argue that it was seperate work rather than looking like it was buying a finished property - so it was more about arguing the law than assessing the numbers)