What to consider regarding rear construction, narrow access paths, and co-ownership

I would: 1. Only buy if there is a high probability of a good neighborhood 2. have the access route registered in the land register as a separate parcel and enter a declaration of indivisibility. 3. Expect higher construction costs if the access is a logistical challenge 4. Fairly allocate the costs of the access route proportionally to the owners and record this contractually. 5. I would only build the house on land that is 100% mine - if the land shares also affect the building site.

1. That still needs to be clarified, but at the moment it is just my pessimistic approach. There are no negative indications. 2. That is exactly the case. The access route is a separate parcel, and only that is divided between the two "house plots". So in total there are 3 parcels. House plot 1, access route, and house plot 2. I would get house plot 2 100%, and the access route 50%. 3. Ok. 4. As far as I understand, the initial creation of the access is my cost item. But the subsequent maintenance is then to be carried out jointly. Currently, the front owner only needs about 40% of the access parcel for their driveway. The rest of the way is still garden/tree area. But I don't think that is so critical. 5. The building plot is 100% mine. Only the access route, as mentioned, is 50/50 with the front plot. That is why I would also like to have a right of way registered on this access route. So that I do not have only 50% decision-making power over the use of the access route, but am really independent in the land register of the moods of the front owner. Or is that too pessimistic?

For contracts that are still supposed to be valid in 50 years, there is no such thing as too pessimistic. Just imagine, the property falls victim to a forced auction or worse: an [Erbengemeinschaft].

There is neither friend nor foe

You can have the right of way registered in the land register. It is legally secured and well protected there. There is absolutely no problem with that.

I am a bit "afraid" that the measurement will show that the access way is not quite 3m wide.

Have the parcels not yet been formed in the cadastre? Are there fixed points for the boundary demarcation that could prevent the 3m width? If the partial area is explicitly described as 3m wide in the notarial deed, the surveyor must also form it accordingly. Otherwise, the regulations of the Building Code regarding defective works apply – which means: surveying will continue until it fits.

The regulation that an access belongs to several parties is common.

That is correct. But where is it regulated that the joint property should be an access? Apart from the easements that the approval authority will require, I would have two rights of way entered in the land registers; one each in favor of each building plot. In the entry authorization, one can and should write down very thoroughly the considerations regarding condition, construction, maintenance, and use. This way, they remain permanently secured and transparent for all parties involved and their legal successors.

Can formulations be included like "The access way shall be permanently constructed as a paved fire department access"?

Yes. Describe the intent as precisely as possible and only leave open where you want to stay flexible.

However, the wall pillar definitely has to be removed to guarantee the 3m for the fire department. How and where would one coordinate that?

You can include that in the entry authorization. The notary will find the right words.

Maintenance costs would always be shared, right? Even if only I have an interest in the complete access.

If the co-owner agrees... In his place, I would have it formulated differently.

Can he object to that?

Definitely make clear regulations in writing, then there will be no objection.

Other things that people often overlook?

Obligation to fence.

That is correct. But where is it regulated that the shared property is supposed to be an access road? Apart from the easements that the approval authority will require, I would have two rights of way registered in the land registers; one each in favor of each building plot. In the registration consent, one can and should write down in great detail the considerations regarding the condition, construction, maintenance, and use. This way they remain permanently secured and transparent for all parties involved and their legal successors.

That's how I know it too - even if you are a co-owner of the pathway parcel. Additional keywords for regulation: (connection to) drainage

Thanks already for all the answers.

Obligation to enclose.

So here specifically agree on who is responsible for a fence?

Upon inquiry, I learned that the parcel has already been surveyed and is supposed to be 3m wide.
So the risk is basically no longer on my side, right? If problems occur, the surveyor is to blame?