Is the Wohnflächenordnung (WoFIV) to be considered during property valuation?

( Are you AA or BB)

Haha, good question (AA) and (BB) are a community of heirs in equal parts. Together with my brother, I represent (BB). We want to prevent our two sisters (AA), together with our brother-in-law, from using the above-described trick to snag our apartment cheaply and sell it for a large profit. Our goal is an amicable sale, which has so far been rejected.

Our goal is an amicable sale, which has so far been refused.

Then I would simply initiate the partition auction. You can still come to an agreement - within the framework of a private sale.

I agree completely. Initiate the procedure immediately. That creates facts.