Financing Feasibility Single-Family Home Purchase

cool, I'm selling my old shack to my tenant; due to the leasehold, he can only securely use it for another 60 years (who is the lessor? The church? Then you can expect an extension, they don't sell land but do leasehold - however, the leasehold would probably be cheaper), I'm having a lifelong free-of-charge(!!!) right of residence registered for myself (and probably my partner) and suddenly I have a pile of money, nothing changes for me in my living situation, but I no longer have worries about any renovations, so I save money. If something is changed, I'll definitely have a say - it's more or less my house, after all.

The young couple is financially supported by dad to the tune of 1/6, but then they grant him 50% of the total ownership - so he also has a say, since it belongs to him half as well.

When the old owner, his partner, and the money-giving dad finally depart this life after a few decades and the property perhaps finally belongs to the (then no longer young) couple (let's just leave any inheritance disputes regarding the 50% from dad aside), then they might have a few years left before the landowner decides not to renew the leasehold. Then the couple, by now probably retired, after the house was finally solely theirs for a few years, will have to move out.

Do you at least feel some frictional heat when you're getting taken for a ride like this?

Update on the situation: We have engaged an expert and he has estimated the value of the house at 600,000 euros through an appraisal. That is already encouraging!

The downside is that the [ErbPachtvertrag] for the land is being renegotiated for another 99 years.

What annoys me a lot is that when my dad supports us with 100,000 euros, he wants to be fully registered in the land register. We now want to sell our current vehicle. Hopefully, we get more than the buyback value from the bank. The all-in leasing is now fixed for 6 months. Unfortunately, the costs for the leasing here increase to 370 euros.

and he has estimated the value of the house at 600,000 euros through an appraisal

The house and land without leasehold, or did he take leasehold into account? If yes, with the new 99 years and the new leasehold, or with the old values?

Taking into account the ground lease and the old values regarding the ground lease.

We have engaged an appraiser and he estimated the value of the house at 600,000 euros through an appraisal.

With land? Taking into account old or new ground lease?

The disadvantage is that the ground lease contract for the land will be renegotiated for another 99 years.

Why? Under what conditions?

What annoys me a lot is that if my dad supports us with 100,000 euros, he wants to be fully registered in the land register.

Then he should get a land charge of €100,000 – thus he is fully secured with his loan in the land register. He doesn’t have to become a co-owner. The bank also only gets a land charge.