Fitness Area Planning

I would personally prefer the basement. I also see no reason not to build it. That way, you don't need as much space above ground. Alternatively - with that monster property - I would build a nice garden shed (if possible from a permit standpoint). Add the sauna inside and the pool in front. A dream for every athlete.

If the extension is really only supposed to cost 30,000 EUR, you will hardly get a (partial) basement for that money, so in any case the extension or even a separate little house on the plot would probably be cheaper. Whether that could really be done all-in for 30,000 EUR is another matter.

We have a small sauna area with a few fitness machines. It required between 25 and 28 sqm, but it could have easily taken more.
For us, it fit so well: It’s on the ground floor (no big deal in a bungalow) and has a terrace door facing north without viewers. Overall, the house is divided into a publicly accessible area and a private one. In the private area are our bathroom, the bedroom, and the sauna area. The path to the shower is short.
Whether to have a basement or not is a matter of taste. But if there is a basement, then nicely equipped, including the lighting. From wellness areas I know that people sooner or later stop going in when there’s a basement feeling. I know several such disused facilities. In the basement, I would consider a ventilation unit. Also regarding the flooring, I would find something well adapted to the use good, perhaps something shock-absorbing.
Best regards
Gabriele

Do you think it will likely not stay at 30,000 euros?! I know that people usually estimate 2000 to 2300 per sqm, but it is not a proper living area.
Would a garden shed of that size plus sauna and all connections be possible for 30,000 euros?!

Would a garden shed of that size plus sauna and all connections be possible for 30,000 euros?!

Would a garden shed of that size plus a sauna and all connections be possible for 30,000 euros?!