I like your approach, Flowerstone. Unfortunately, the space requirements including the basement combined with the targeted budget do not quite match the current construction costs – as several have already written. You have nice hobbies that create space requirements. The idea of fitting everything into the house is obvious but also very costly. One approach is to consider which beloved activities that contribute to the goal of "good quality of life" can find a place outside the building. Parties: from spring to autumn in the garden where a carport provides protection and shade. Birthdays in winter? You can very often rent rooms (from parish centers to star hotels) until you reach the cost of a party room in a basement. Horse stuff: Most of it can also go into a good garden shed, which causes significantly lower space costs and provides additional benefits. Musical instruments: Depending on what you play, that’s not so easy. A piano fits in the living room; a drum set at home makes it a bit more complicated. We have a Clavinova, an electric bass with amplifier and speaker, a cello, and a guitar in the living room. Non-ugly equipment helps. A cello is permanently “loaned” as a form of “support” to a musician. A son also plays electric bass and has three hanging on the wall in his room. It's worth it to him. The electronic drum kit fell victim to our downsizing during construction, but we don't have a really enthusiastic drummer anyway. Sauna and spa: That’s something great – and truly a luxury. If you calculate the construction cost for the space requirement in the basement, the spa area becomes more expensive than the living room and kitchen. Is it worth it? A whirlpool and a sauna barrel can always fit later in the garden if it becomes clear what the house really cost. It’s also nice that the costs don’t arise simultaneously. Flexibility and safety: Yes, if the second (or third) child turns out to be twins, you just deal with it when that time comes. I wouldn’t rush into architectural expenses beforehand. The same applies to an age-appropriate bedroom.
These are just thoughts that may or may not apply. The core of my message: If you confuse wishes and goals when you start planning, it becomes expensive. With a flexible wallet, that’s no problem, but as soon as budget discipline is required, it’s very wise to consider what fundamentally determines quality of life. Some have decided not to build themselves and to buy something large and used and less “perfect” in detail to reach their goals. Others have focused more on the essentials and built accordingly. Many talk about “renunciation” when no spa or dressing room is integrated into the house. OK, if you want, you can make yourself unhappy while fulfilling a dream. I consider such an attitude detrimental to good quality of life. I did not buy half a yacht last year and canceled the plan with a friend to sail the ARC from the Canaries to the Caribbean. That might cause a bit of nostalgia, but the quality of life remains, which alone in the time investment for preparation over two years would probably have been lost. Is that “renunciation”? Certainly not. Is not realizing a party room and spa area in the basement of a new building “renunciation”? Certainly not either. If it should feel that way, there is a 99% probability that wishes and goals have been confused.