Construction cost estimation of a semi-detached house experiences

@ Thanks for your answer.

I assume the €15,000 is for doing the painting and laying the floor coverings ourselves. Those are definitely tasks we would trust ourselves to do. The €40,000 for additional furnishing has initially been estimated as a percentage. There are certainly savings opportunities here. But I have to be honest: You can't live without a kitchen, though. Even if this amount is halved, the total costs won’t decrease significantly.

For me, it is more important how much personal contribution can still be made or how construction costs can be saved. It doesn’t have to be a turnkey house for us. We are happy to help and work independently if that reduces the financing.

To go back to the finances: We are 33 and 29 years old and therefore have somewhat more time than average for financing. We manage well with our current income with one child. We have no debts, we don’t pay for a car (I have a company car). The problem in the financing area, however, is that I have a sales job. The assumed €4,900 net are calculated conservatively. On top of that, there is an annual special repayment of €2,000-3,000. In good years like now, the special repayment can be increased up to €25,000, but that is not foreseeable every year. The problem currently is more that I earn well, but as a result fall out of the NRW.Bank funding. Therefore, alternatives have to be found for how interest costs can be lowered. The KFW40 funding for families only helps in the first 10 years with low interest on a partial amount.

You want everything, low interest rates, no risk, affordable house. Somewhere you have to make compromises. Do not underestimate the effort and the time and money that personal contributions cost. In addition to job and child, you have to think that through carefully. Despite the rather young age and above-average income, you have little equity. Where did the money go? Would you be disciplined when choosing the house?

How much personal effort can be expected from a building owner?

From none at all up to building an entire house. The classics are the walls and floor coverings. Unless you have friends who actually always have enough time exactly when you need them (electrician in the family etc.).

We could also cover individual trades through my brother-in-law. We have some contacts there. Would that help?

Awarding individual trades can help. But you also need someone (an architect) who manages everything for you. A layperson should not do that alone just to save money. And please remember that the price of the house is primarily determined by you yourself. The respective craftsman only does what you tell him. But if (and especially with awarding individual trades there is the "risk") you keep having new ideas on the construction site during the building phase (and/or proposals come from the craftsman), it can get expensive.

The €40,000 for additional furnishings was initially estimated as a percentage. There are certainly opportunities to save here. But I have to be honest: you can't live without a kitchen. Even if this amount is halved, the total costs do not decrease significantly.

There lies the crux of the matter. €20,000 is a lot of money; it only seems less when dealing with financing of that magnitude. How long do you have to set aside surplus money to have €20,000 saved up?
And that’s how the entire construction adds up. Then there’s the nicer switch series or the larger tiles.
And for €20,000, you can already get a lot of kitchen if you don’t blindly go into the kitchen showroom with the trendy wish list.

You want everything: low interest rates, no risk, affordable house. You have to make compromises somewhere. Don’t underestimate the effort, time, and money that own contributions cost. In addition to job and child, you have to think about that carefully. Despite the rather young age and above-average income, you have little equity. Where did the money go? Would you be disciplined when selecting the house?

I think that sums it up quite well. Of course, we want a lot. Who wouldn’t want that? That’s why the question is what is affordable? And what should you prepare for and what should you give up? We also want to pay off our project. On the subject of little equity: When I look around my circle of colleagues, we actually have quite a bit of equity. Where is the money? In life, in taxes, with the child, and with expensive housing. People study longer nowadays, and I have had my full income for only three years, before that rather an average income. My wife works part-time for minimum wage. She likes the job, though.

Regarding discipline: We are quite good at that. When budgets are set, they are also adhered to.



Then we should probably stick to floors and painting work first. There are definitely warranty risks with own contributions as well. I could only imagine that we save on individual trades since our family has quite good contacts in the area. However, how much can be saved here is rather questionable. We could hire an architect for that, my brother-in-law can support as site manager and also renegotiate. Still, the rule applies here as well: "What costs nothing is worth nothing." Trades that are negotiated down to the bone will not deliver solid work either.

With the assumed costs of €840,000, I am rather unsure whether such a construction project can be paid off by retirement. If I reduce the second buffer and additional interior fittings, about €800,000 still remain. Of course, wages rise, funding opportunities or also an employer loan could be explored. I am satisfied with my job. I still have good promotion prospects. But interest rates in the long term are also uncertain. According to my review, subsidies tend to support those who couldn’t afford a house anyway. KfW loans have high interest rate risks after 10 years. What is the best way to approach this topic? First explore funding possibilities and look for advice from financial consultants? The topic of how much house you can afford is currently rather hard for us to grasp and involves many variables that are not always foreseeable.

With about €82,000 equity by 2025 and already generously estimated loan installments of €1,800 with a total monthly income of €4,900, financing is, as far as I can see, rather hard to foresee. Special repayments (€2,000–3,000 per year) don’t help much either. For ongoing ancillary costs we have calculated about €520 and maintenance €140. Vacation and Christmas bonuses and other income sources per year of around €4,000–5,000 net are not considered.

And now?

and already generously estimated loan installments of €1800

But that is per se only a loan of +/- €430K (calculated with 3.5% interest and 1.5% repayment - I went for a longer fixed interest period, KfW Family also offers 20 years. 10 years fixed interest with KfW Family currently means "only" 0.86% interest + at least 3% repayment). Therefore, the project should (unfortunately) be off the table anyway.
You can only handle the necessary volume with a significantly higher installment.