Buy land with inheritance advance

Replace in the specific case of the OP the rent with a leasehold - now over & out, as we want to keep a proper distance from legal advice (which works all the more efficiently the more clearly the questioners recognize the gaps for thinking along).

The replacement may not help much in some cases. There are family courts that consider any transfer of land and real estate to children as legally disadvantageous.

Did I miss something? This is about adult children, right?! They are allowed to receive gifts or, presumably, are allowed to decide for themselves whether they are up to the responsibility?

I understand it as @Birkenfelder is building the house he is now constructing on his parents' property,

You must have misunderstood: the property belongs to an unrelated third party and is purchased with money that the OP is gifted in advance ("with a warm hand") by his future testators.
So, let's assume – any resemblance to is purely coincidental – Bommes once had a buddy who, together with his lawyer-notary and a few other regulars, discussed such strange things as jump inheritance, bought a property, leased it to his children under a hereditary lease, and built on it. Furthermore, let's assume Bommes’ buddy was burdened with the condition to exempt his current child from charges and, if necessary, later find a solution for equal treatment of his future child. But now really, good night John Boy, taps for the fairy-tale hour.

Hello,

I think a lot is being interpreted here. So let's go over the facts slowly again:

1. My wife and I (we have a child together) were offered a piece of land by a third party to whom we are not related
2. The land price X would be provided to me by my family in advance as an inheritance advance (instead of a bank loan, which we could also take out)
3. I will pay for the land with the inheritance advance

4. Question: who should be listed in the land register?
4.1. Me because the land was paid for with my early inheritance (disadvantage: my wife is not listed even though she will contribute to a future house)
4.2. Both of us with a marriage contract stating that in the event of divorce and sale of the property, the land price X will not be taken into account?
4.3. Another possibility?

5. For the house, we would then take out a loan from the bank

This is not about putting a house on my parents' land, the land is being purchased by me with my inheritance advance (I could also buy other things with the money). Also, I would not want to evade taxes if any were to apply. However, I assume this is not the case since the land price is below the exemption amount of 400,000€.

Oh dear, I was not aware that this could be interpreted so differently than I originally intended. Sorry!

Edit: I am very grateful for any advice, which of course does not constitute legal advice!

No, that was understood correctly, don't worry.
I just forgot in between.
But it didn't make a difference for my question (offtopic, sorry for that).
Actually, it's logical that you can't "gift" your children debts, but it wasn't that clear to me.

I also would not want to evade any levies, if any were to be incurred.

Exempting the children from this only means that you do not subject them themselves to this payment burden, evasion was not mentioned.