Which financing option should I choose?

So, I also inquired at VW Financial Service on the side. They do the same as Dr. Klein. And the advisor was honest from the start and said that the value of the property will be reassessed after the savings period. In my case after 15 years, and if it turns out that the property no longer covers the value of the loan, they can refuse. The creditworthiness will probably also be reassessed at the time of the loan.

At least this was not the case with Aachener. The property played no role, or only insofar as there was one. Saved up until January 2017. Allocated. Form, what should happen? Payout or payout plus loan? With or without additional allocation? No land register entry, nothing. No inspection of the property. I could have also used the money to acquire a conservatory. Or for the renovation of an old building. So, the uncomplicated nature is the advantage of building savings. But the disadvantage is the fixed interest rate at the time of contract and the high equity share required to get the loan, 50% in the classic form. As I said, option two is the wiser one for you. Karsten

So also here as well: How about paying off and throwing the building savings contract in the trash? I have nothing against building savings, God knows, I even think it's good. But not at this amount and for owner-occupied housing.

Definitely take the KFW loan and secure it with a 30k building savings contract (without account management fee! instead of 25k). Otherwise, rather 15 than 20 years fixed interest period with 2-3 repayment changes and at least 5% prepayment penalty. As an alternative to Ing: Degussa or DKB.

The Ing-Diba is quite relaxed when it comes to construction loans. But I still kicked them out rather harshly. And it seems to me that brokers and banks have a commission problem. Or why else do they offer interest-only loans over 15 years or even longer?

Just to illustrate the interest over 15 years:
283,300 at 1.99% and 0% repayment: €84,565.80
283,300 at 1.99% and 2.5% repayment: €67,125.01 (monthly rate €1,060.01)
Difference: €17,440.79

And remaining debt at 1: €283,300, at 2: €159,623.21
With 1 you start again at the beginning and you get a few more years of interest payments on top. Even the engineer should use an Excel spreadsheet for interest calculation. That helps more than the wild listings from financial brokers. I speak from personal experience!

The monthly rate comes about one way or another, only the interest paid in the end and the remaining debt differ quite a bit sometimes!

Why exactly the BHW, I can't really say, Dr. Klein just suggested it. What I didn’t know about the building society savings option is that, in the worst case, the building society can refuse me the loan. And if I already read here that BHW is unreliable, I'd rather keep my hands off it.

Nonsense, BHW is neither unreliable nor do you have problems getting the loan there. I personally know a case where BHW saved the construction loan for a woman in distress through no fault of her own with a child (the father passed away, due to his heart defect he had not obtained risk life insurance). Problems with BHW may occur if you simply stop payments instead of contacting them early on in case of unexpected problems. I don’t know how anyone can come up with the nonsense of calling BHW unreliable.

Regarding the procedure: In case 2, the building society savings contract is assigned, i.e., transferred to Ing-Diba. As soon as the building society savings contract is ready for allocation and the agreed fixed interest period with Ing-Diba has expired (or a few weeks beforehand), you will be asked to accept the allocation and apply for the building society loan. For loan amounts over 30,000 euros, this is of course not unsecured, but secured by a land charge; however, Ing-Diba transfers the land charge owed to them (possibly proportionally) to BHW. In between there are such great documents like “in trust” etc., but you don’t really need to worry about them. In this setup, you are basically 100% protected as long as you do not default on payments. And as soon as the building society loan takes effect, you can make any special repayments at any time. Unlimited in number and amount and without impact on the loan interest rate. Thus, this setup definitely has its advantages.

The loan is always interest-bearing as agreed at the conclusion, the credit is always without land register

Wrong! Building savings loans are also secured in rem (in the land register), unless there are substitute securities (rare) or loan amounts under 30,000 euros. Usually, the borrower does not notice this, as the in rem security was already included in a bullet loan, for the repayment of which the building saver is assigned (ceded), and this land charge accordingly passes to the building society.

Just to illustrate the interest over 15 years: 283,300 at 1.99% and 0% repayment: €84,565.80 283,300 at 1.99% and 2.5% repayment: €67,125.01 (monthly rate €1,060.01) Difference: €17,440.79

And remaining debt in 1: €283,300, in 2: €159,623.21 In 1 you start again from the beginning and a few more years of interest payments accrue.

With 1, however, you are saving up a repayment substitute (often a building savings contract), so you don't actually start again at zero. Only the interest on the credit balance is usually negligible nowadays. Therefore, you have to calculate whether you are buying security until the end of the financing by paying "more" interest. There are also banks where bullet loans have a lower nominal interest rate than repayment loans – then the difference disappears or at least becomes smaller. By the way, KfW is not one of them, as the bullet loan there has the highest nominal interest rate.