Floor plan of a single-family house with 4 children's rooms and a separate apartment

Thank you very much in advance for your assessment / contributions

Is the granny flat intended as a 4th children's room, otherwise one is still missing?

No, it is planned on the ground floor

You cannot build the house with your budget...

I received an offer of €450,000 turnkey and will deduct about €30,000 for own work

I'm not sure if you are allowed to build that large. The ancillary facilities are also included. can you please take a look at this?

According to the architect, we are within the building window (see pictures)

[QUOTE="nordanney, post: 428187, member: 14669"]
It is probably the room on the ground floor (utility/sleeping).

Almost 300 sqm area (including living basement) for the desired €420k including photovoltaics, kitchen, fireplace and whatever else. Respect! Normally, we always calculate €2.xxx per sqm of living space + basement + ancillary construction costs + equipment + garage/outdoor facilities. That doesn't add up.

According to the builder, he can keep to the budget!
The land purchase is in 4 weeks and if the costs don't fit, then the journey will probably continue without a house [/QUOTE]

What is included in the offer and what is not listed?
Basement in living space quality, earthworks, what equipment? Additional building costs

remove the basement. Then it fits the budget.

The building envelope is not the floor area ratio. The floor area ratio may be exceeded. I don’t know exactly how that is calculated and what is included.

I have received an offer of €450,000 turnkey and will deduct approximately €30,000 for own work

Please take this with great caution. €30k own work is a lot if you are building with a general contractor. What exactly are you doing? What is included, what is still missing with the general contractor – in other words, what does turnkey mean (normally floors and walls are still missing – at €30 per sqm for floors as well as priming and painting or wallpapering, it will definitely be a five-digit amount)? Being within the building window does not mean that the site can be fully built with three full floors. For that, there are floor area ratio/plot ratio regulations. The floor area ratio of 0.55 on a 435 sqm plot means that all full floors together may be a maximum of 239 sqm in total (with certain regulations in detail). Does that really fit with you including the granny flat?

From the turnkey offer for 450k, I would like to see the construction service description. And how exactly do you plan to save 30k with own work? Are you a craftsman? Can you handle an entire trade completely on your own? How much do you still have in the budget for incidental construction costs (including earthworks), carport, outdoor facilities, etc.?

Be sure to draw in the existing and desired furnishings on every floor plan.

The bedroom on the ground floor is already quite small. It doesn't have to be a kids' room with an integrated roller skating track, but more than a bed and a wardrobe won't fit.

The dining table looks quite small. I assume it's similarly hectic with you as it is with my friend. Sometimes a few more children join for meals.

In the bathroom upstairs, there is no storage space for towels and such. The passage from the sink and shower to the toilet is quite narrow.

Why does one children's room have [die Kleine Schräge]? The children's rooms upstairs are twice as large as the small cubicle downstairs.

I received an offer of €450,000 turnkey and am deducting about €30,000 for personal contributions

The question is always what "turnkey" means. We "built" our townhouse in 2001 "turnkey" and deducted personal contributions for the interior work. For "turnkey," the exterior work meant: access path to the front door paved in width and terrace (5.75 x 3m), plus roll lawn up to 1m from the property boundary. We then did not consider this as "complete." Turnkey even came with the cheapest tiles and unplastered concrete ceilings. When deducting personal contributions, you must not use the seller’s prices as the reference figure. They don't give you any margin. Rather calculate deductions below the construction price. Furthermore, it is always a question whether the budget represents the wish or the limit of what is feasible. If the latter is the case, sleepless nights are preprogrammed and most people build a house to improve their living situation.