2 buyers - 1 property - different amounts of money - owner?

Then person A buys the apartment completely and lets person B use it free of charge. Problem solved.

... and I would like to add that A should consider making a contract with B regarding the payment of the annual ancillary costs (water, property tax, heating, etc.) or does A also want to leave that free of charge?

And I don't understand the problem itself. A is/will be sole owner or majority owner and B lives in the apartment rent-free. So what?

.. whereby the 5% share, which has always been talked about until now, is also not understandable, and could at some point really cause problems.

The reason why Person A mainly pays for the property is that Person B has more money than Person A. However, Person A is supposed to have their main residence in the property. So Person A lends Person B their property in large fractional shares.

I can only see the picture now.... Everything is fine with the purchase. With the financing, I don't understand it again. A takes out their own loan and B also? You need a bank that agrees to that – then those would have to be equally ranked fractional mortgages. It becomes a complicated construct to arrange the financings. As a bank, I would want broad purpose declarations so that everything covers everything and everyone is liable. Then the division of ownership ends up being nonsense. And if it is ONE loan, the division by fractions becomes irrelevant because then both are fully liable.

What is the real reason behind these thought processes / this confused construct? The fear of being taken advantage of? Wanting to secure someone "cheaply"?

If I can buy a property with 95% certainty and start making such (mental) contortions about whether and how to consider a second person, I would rather pay the remaining 5% of this property alone and thus create clear financing and ownership conditions for myself and the other person regarding this property. Then no one is taken advantage of, neither person A nor person B. The non-owner can be granted a usufruct right for a certain period or for life, as well as regulations regarding ancillary costs (by notarized contract / will), if this is desired by both parties.

If it is about the "cheap" security of a non-related person, I go to a neutral financial or tax advisor or lawyer with whom I develop a simultaneously secure and as inexpensive as possible construct through which the non-related person can be permanently secured. This could also be done, for example, through various types of investments, foundations, etc. etc.

Conclusion: Behind this – excuse me – mess lies another motive. That must be clearly worked out, then a fair and cost-efficient solution can be found.

A non-owner can be granted a usufruct right for a certain period or lifelong, as well as arrangements regarding ancillary costs (by notarial contract / will), if this is desired by both parties.

Just no usufruct. Otherwise, he/she moves out, rents it out, and pockets the rents while the owner is left frustrated. Usage agreement with ancillary cost agreement. That’s all there is to it. Because if you no longer get along later, you can separate easily or the owner can simply kick out the partner called a "freeloader."