Really? Schufa was the first thing anyone asks when I was interested in a new apartment. My schufa score is abysmal, but luckily the score is not included in this document, only the negative entries.

50/50 may hold true if you are renting directly from the owner. If a real estate agent is involved (or something like degewo) it is somewhere around 100% of all cases.

+1 for owner. Luckily you can choose (still).

Not all the time probably, though in my experience, especially if it's not a flat share but a proper apartment, it's definitely closer to 100% (Berlin).

I guess the likelihood increases if you go through one of the newer screen-tenants-first-online-platforms or the building has hired a property management company. Going through newspaper-classifieds or owner-let apartments yielded 100% no Schufa for me in Munich + Berlin.

see this information https://www.settle-in-berlin.com/what-is-schufa/