Purchase advice / Financial evaluation - 1950s house with attractive plot

What should go into the "new" bathroom? Bathtub, 2nd WC? Or should it just be bigger? Maybe a narrow strip of light at the top of the new bathroom wall could bring light into the hallway? The idea via the staircase is also good, there are nice apartment entrance doors with glass inserts, or maybe a strip of light next to the apartment door? Could you perhaps convert one of the rooms in the basement into a "wellness bathroom"? Then you would have 2 bedrooms plus a shower bathroom plus WC on the ground floor and a spare room plus a nice large bathroom in the basement. With one child, the space upstairs is easily enough, 2 smaller children share the bedroom, later another bedroom will be set up in the basement. Or you could include the upper floor (tenants are over 80, it is estimated it will take a maximum of 10 years until they move out). Or is that not possible in the basement? The plan for that would be helpful!

Regarding the kitchen breakthrough: leaving a piece of wall in the middle could also look good and help structure the new large room a bit. You could set up a cozy small dining area on the kitchen side. The large dining area would then go into the current conservatory, and you would have to carry all dishes through the living room area; with children, that can be annoying if you have such "long" routes multiple times a day. Furnish the new large open-plan room to see if and how it could be nice and practical. Is the TV spot fixed? Then you could place the "dining" area near the kitchen. Stove: I would put it in the living room because it’s simply nice to watch the flames. Is there a free chimney flue/ chimney, and if so, where?

And what about the rooms labeled with dining and bedroom? Should that remain?

In general, the amount of information is too limited for more than fragmented advice.

What is supposed to go into the "new" bathroom? Bathtub, second toilet? Or should it simply become bigger?
Maybe one could bring light into the hallway through a narrow strip of light at the top of the new bathroom wall? The idea via the stairwell is also good; there are nice apartment entrance doors with glass inserts, or maybe a light strip next to the apartment door?

We would definitely plan for transom windows at the top of the bathroom facing the hallway. Also coming from the apartment door would be useful. We'll include that in the desired state.

Could you possibly convert one of the rooms in the basement into a "wellness bathroom"? Then you would have 2 bedrooms plus shower bathroom plus toilet on the ground floor and a spare room plus a nice large bathroom in the basement.

Yes, that would be possible, see basement sketch. We have already considered that, but nothing we would do right now.
The question is really whether we should plan without a bathtub for now and then do something in the basement later.

With one child, the space upstairs is plenty, two smaller children share the bedroom, later another bedroom will be established in the basement. Or you could add the attic (tenants are over 80, so it is estimated max. 10 years until they move out).
Or is that not possible in the basement? A plan for that would be helpful!

Yes, we should expand both in the basement and the attic (as soon as the old tenants have moved out).

And, what about the rooms labeled as dining and bedroom? Should those remain?
In general, the amount of information is too little for more than piecemeal advice.

We do not have children yet, I think there will be no more than one (my wife is already 36).
We are now planning with 1 child's room, meaning that the current dining room would then be used as child’s room/home office.
All other rooms can be put to use space-wise.

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In the latest design, I planned differently and moved the bedroom into the current kitchen so that the kitchen and living room don’t stretch so far in length but also gain width. Additionally, the living room could then be equipped with a fireplace.
Where there is one shown now in the living room (former bedroom), there is an unused chimney in the corner.

Attached now are 3 floor plans again:
- 1x original state ground floor
- 1x basement (the two habitable rooms are marked in red)
- 1x newly planned ground floor with child’s room

And 3 pictures showing how the new layout in the living room and hallway would appear.

In the latest draft, I planned differently and moved the bedroom into today's kitchen so that the kitchen and living room are not stretched lengthwise but more in width. In addition, the living room could then also be equipped with a fireplace. Where one is now pictured in the living room (former bedroom) there is an unused chimney in the corner.

First of all, I like the new floor plan; with 1 planned child, it fits, the home office can move to the basement later. The open space is actually no longer so narrow, and the fireplace is well placed here if the chimney is in the current bedroom. However, that is probably crazy budget-wise if so many walls are removed/relocated/rebuilt. In addition, a completely new bathroom including dismantling the old bath/WC (both of which are actually relatively new and really wouldn’t need to be new yet), a new kitchen (which really can be new!), a new nice fireplace, new floors (aren’t those relatively new too?), new apartment door/front door that brings more light into the hallways... Unfortunately, energetically nothing has been done yet; ultimately, those are all “just” optical/functional improvements. Hopefully your architect knows the current construction costs and can clearly tell you whether your budget is sufficient or not. The 2 rooms in the basement are unfortunately trapped, but if you enlarge the bathroom upstairs, you don’t really need another full bathroom downstairs. I rather see a laundry room there, possibly a WC (very practical with kids in the garden) and a small home office (the WC is also useful here). And when the tenants upstairs move out, the question is whether you want to use it yourself or actually keep renting it out? The number of planned and realized children obviously also plays a role. 36 is no age nowadays if you quickly start family planning after buying the house :), but children really don’t come according to plan :-(

Yes, the costs will definitely be a problem. I think we would do it step by step. Over the next 3 months, we will save some more money, let's see how it looks then.

Some things could be planned, but they might possibly wait:
- Windows in the stairwell not yet
- Entrance door not new at the beginning
- Oven also only next year