Hi. It's taken us a long time to look at this, some questions. Seems we have 3x options:

a) Do nothing, pay whatever per-year that they adjust it to
b) Pay €1.200 now to pay € 1.284/yr (indexed) as of 2024
c) €1.200 now + €45.338 to pay nothing going forward

So, maybe I'm wrong about this, but in reverse order:

c) It seems to me that this makes no sense. If I have 45,000 to spend today that's an average of 1300-1800 EUR growth/yr assuming 3-4% long-term stock market returns (which is very conservative). I.e. I don't see the opportunity cost of paying one lump-sum now making sense.
b) Maybe this option makes sense, is that € 1.284/yr the "at most" or "it's this" amount, i.e. isn't whatever amount it's going to be per year unknown now, or indexed to housing price? Are there any projections as to what it's likely to be in the future? If it's going to be a few hundred EUR more than 1284/yr (and growing more than inflation) I can see paying the notary cost now to fix it making sense
a) Depending on "b" maybe we should just do this...