Design of building owners' association

The plan is that we (my wife and I) will buy the property. The costs for the house will be shared 50:50 with my son. It is intended to be used as follows: garage and ground floor apartment by us (rental), the apartment on the upper floor by my son, owner occupancy. If he no longer wants to use the property, the possibility should exist to sell to us (right of first refusal), otherwise to sell or rent it out. The son is 24 years old and should thus have an economically viable yet flexible start in the real estate world. A solution is sought for the son that can be financed through a bank and causes as low costs as possible.

That is contradictory, because if you and your wife buy the property and are registered as owners in the land register, then you do not need a right of first refusal.

Or is "property" meant literally – the property is supposed to belong to you, a heritable building right agreement is made, and the son becomes the heritable building right beneficiary, while you remain the property owners?

The plan is that we (my wife and I) will buy the property.

Then you will also be the owners of the property. Your son owns nothing.

We split the costs for the house 50:50 with my son

Then you remain the owners of the property and additionally of the house. Your son still owns nothing, but he has debts.

The usage should be like this: garage and ground floor apartment by us (rental), the apartment on the upper floor by my son, owner-occupied.

Thus, you will be landlords for both apartments for tax purposes.

If he no longer wants to use the property, there should be the possibility to sell to us (right of first refusal), sell elsewhere, or rent it out.

That is not necessary since you are already the owners. Your son is basically the tenant.

The son is 24 years old and should have an economically viable and still flexible start into the real estate world.

Your son gets pushed into financing part of the house at the start of his real estate journey but has no assets to back it up. Not a good start.

We are looking for a solution for the son that is financeable through a bank and causes as low costs as possible.

The bank you mentioned has already offered the solution. The son gets a loan and the entire house (= your property) is liable for it.

Conclusion: An unpleasant situation for the son who gains no benefit and co-finances your house. For you, it can become unpleasant if the son can/will no longer pay and the bank can force the sale of the entire house in foreclosure.

More expensive, but clean, is to divide the house into condominiums so that each party only has to finance their apartment. I suggested that from the beginning.

Hi Moin I have not seen it like this before, but it is logical since the house is an essential part of the property. What is the procedure to reach the goal we have in mind? Buy the property and register the son in the land register immediately? Then build the house and divide it into 2 condominiums (notary)? We buy the land and build, then sell one apartment? I will arrange an appointment with the notary / lawyer we trust. Olli

We buy land and then build and sell an apartment?

The apartment can certainly be sold during the planning phase. Keyword "property developer". Then there is a payment plan for the son depending on the construction progress. For the bank, it is a purchase of a condominium.

Hi
Then, nonsensically, real estate transfer tax applies. Costs that we want to avoid if possible.
For the bank, the solution we initially considered is also not a problem at all.

Olli