Financing - which construction financing is sensible?

Not only does a later transfer incur new real estate transfer tax (then on land and house) as soon as there is a land charge on it, the banks also get involved in the deal.

The transfer of ownership between spouses is exempt from real estate transfer tax in the case of community of accrued gains. The bank should not pose a problem if the wife has her own income and enters into the loan agreement. I wouldn’t worry too much about that initially.

Splitting into 15 and 20 years seems unfortunate to me. A 100k over 10 years with a max 30k residual debt would be better. You can get 30k unsecured with good creditworthiness and security. You would have to calculate whether this fits with the planned installments. But generally, I would advise against it in your situation... marriage, children, loss of equity. And the current loan-to-value is already under 60%, right?

Furthermore, you urgently need to think about your internal arrangement. Separation or death must be clarified beforehand in this constellation. Especially if your girlfriend participates in the repayment, but externally everything is in your name.

I would put the marriage (or rather the not yet completed marriage) aside for now, because nothing automatically changes through a wedding.

You remain the debtor to the bank, but also the owner of the house, just as she will have nothing. Just as a note.

My second note would be the mentioned house price of 300000€ [300000€].
Sounds realistic, but there are still additional construction costs as well as the exterior facilities (paving, terrace, enclosure).

However, if that is already included in your calculation, then 300000 [300000] is clearly too little. I assume a 150 sqm house with average equipment.

The house price including the slab is approximately 300,000 EUR.

Don't forget all the additional costs, there should also be something like a kitchen installed, paving, the house has to be surveyed. Depending on the requirements, several tens of thousands of euros can quickly be added on.

In the early days of the children, I would still benefit from the better tax class.

In what way? The tax classes on the tax return have no influence on the taxes you pay; they are only a prepayment. It only becomes interesting when it comes to parental allowance; here it might be worthwhile to choose tax class 5 before the child arrives.

I mean that I still receive her tax allowance if she does not work and has no income.

300k includes additional costs. I already have the plot of land – next to it is my parents' house, meaning the fence, paths, terrace, etc. are all already in place. I also have no earthworks left, as I had them prepared two years ago and have already paid for them. I originally wanted to build with solid construction and already had the building permit. But then my mother unfortunately became ill and passed away. Meanwhile, I now prefer to build a prefabricated house, and I have the offer plus a 20% buffer. And that puts me at 300k.

However, I do not understand the loan-to-value ratio from .

I mean that I still receive her tax-free allowance if she doesn't work and has no income.

300k includes additional costs. I already own the plot – next to it is my parents' house, meaning fence, paths, terrace, etc. are all already in place. I also have no earthworks to do anymore because I had that prepared and already paid for two years ago. I originally wanted to build with solid construction and already had the building permit...

I don’t understand that. Do you already have the foundation, or does the slab not need one? Utility connections are only coming now... then the wastewater management for rainwater, just as an example. The terrace at the house – that will only be built once the house is constructed, then the house surroundings, a lot of money goes there, doesn’t it, or are we talking past each other?

So then, a simplified bank calculation for the loan-to-value ratio: this represents the bank's risk for the loan. If your numbers are correct: Land + House: 170k + 300k = 470k 20% safety margin: 470k * 0.8 = 376k This is the 100% loan value. You need 230k, so 230k * 100 / 376k = 61.2% loan-to-value ratio. Since the land probably has a slightly higher market value than stated by the probate court and there are one or two additional personal contributions in the house: I would definitely pressure the bank to apply interest rates for 60% instead of 80% loan-to-value ratio. That means a few tenths of a percent less interest again. Then the money has to be enough! Otherwise, any additional financing will become really expensive -> see note