Renovate duplex roof + general decision-making aid for house purchase

Hello,

I already had a thread further down about an extension to a semi-detached house.

Now another house has come up for us, which is initially 20,000 € cheaper and almost 20 sqm larger plus the same amount as a basement extension.
However, quite a lot is in much worse condition than in the other house. What would need to be done:
-Bathroom (previously a minimal version in the basement) to be completely newly installed in a part of the existing (basemented) extension there (so far no sewage/water pipes there) -> What price ranges should we calculate? Could there be problems with laying the pipes or is that possible "everywhere"?
-The roof is still old (without overhang) and uninsulated -> Can the "half" roof of a semi-detached house be completely renovated including the installation of a gable without any problems? What price range?
-At the same time, the attic should be properly converted; you can get there directly from the children's room and I imagine that in perspective this part could then be used by the child, e.g. for sleeping, and the lower room part (only about 10 sqm) for playing, schoolwork etc.

If a second child comes, we would add a floor on top of the extension. That would then be about 18 sqm. Price range?

I know it is difficult to make general statements. But we are really weighing:
a) small but fine semi-detached house with double carport (which would have to be moved at some point) where you definitely have to extend (then immediately 2 rooms on the ground floor), with a covered ground-level terrace present but, for example, still a toilet would have to be retrofitted in the very chic tiled bathroom; 2 bedrooms would be on the ground floor next to the living room and one upstairs next to the bathroom; already converted attic serves as hobby/guest room
b) larger semi-detached house with corner plot which looks somewhat old-fashioned and is not yet in such good condition; extension could possibly become relevant with an additional floor and then all 3 bedrooms are on the upper floor

Plot A has a large pond, which we don't actually like much because of the child. Otherwise seems smaller than the other although there is only a 15 sqm difference. However, it is nicely planted so that it is private but also shadier. Purely ornamental garden, whereas I would also like some utility garden with, for example, fruit trees. Covered terrace at the house.
The gable side of the semi-detached house faces west.
Plot B is a corner plot (1 neighbor less, but more winter maintenance and possibly local charges; lamp post is also there) and therefore seems bigger. No car access and carport yet, but feasible. Seems bigger than the other and at least has an apple tree. Still quite visible, I would at least let the hedge grow higher on the two street sides. There we have already talked to both neighboring plot owners and got a nice impression. The gable side of the semi-detached house faces east. Is somewhat closer than the other to a railway line and faces it. It's not really disturbing but occasional freight trains are more noticeable than at the other one.

Hmm, how would you decide or what would be decisive criteria for you?
Cheaper house with more renovation work (although not everything would be necessary immediately, theoretically you could move in with one child like this, although I would do the bathroom right away).
Or 20,000 € more for a small gem, which is already too small even with one child and therefore immediately requires a larger extension? Which would shrink the small-looking plot even more (by the way, we are talking about 600 sqm)? Some other small things would also have to be changed. Everything is designed for a couple, not a family.

Corner plot? Plot "in the middle"?

With B (the cheaper corner plot) I am mainly attracted by the basemented extension. For us, an extension would only be an option without a basement for cost reasons. But with that room you have a lot more storage space, which we can really use!
What do about 20 sqm of basement on a flat plot cost (approximately)?
Our gut feeling unfortunately helps us little. House hunting in our town is nerve-wracking and without compromises it will never work in our desired area.

Sorry for the long text. Feel free to just answer individual questions! ;-)

Are you deciding alone without expertise? That’s how it sounds to me.

I would have an architect inspect both houses to see if the renovation plans you have in mind are actually feasible: on the one hand technically, and on the other hand according to the specifications of the [B-Plan]. You need an architect anyway for the building applications; they should already be advising you now. They can also tell you how and what costs will arise.

Basically, it would annoy me to put a lot of money, work and time into it only to find out later that everything is actually very tight.

Had a professional with us for the small house and also inquired at the building authority - basically, our project seems possible. The same goes for the additional floor in the other house. Unfortunately, there is no time to think about it for weeks in our town, as all houses are selling like hotcakes. Would you therefore tend towards the bigger house? Are there any other opinions? We have to decide by Tuesday, as I actually wanted to submit the loan application for A by then (the other offer just came in now).

If I understand you correctly, then you have to do more renovations in the larger semi-detached house, but I have not yet inspected this semi-detached house with an architect/expert, only the smaller property, which doesn't require much renovation? :rolleyes:

Yes, that's exactly how it is. Well... why do I need a specialist to tell me that a bathroom needs to be created? And that the electrical system needs to be renewed? I know and see that myself as well. I have to say that the real estate agent is basically a colleague and I at least trust his expertise. My husband, on the other hand, is a trained bricklayer and also has his professional eye on it. What extensions and additions are possible in this residential area we see when we walk through the streets. Is it common for you to take an expert to EVERY house viewing? Not here. Who exactly is the right expert who can tell you all the costs at once? Moreover, without having to hold out their hand at every viewing themselves?

Who is the right expert who can immediately tell you all the costs? Moreover, without having to stretch out their hands at every inspection?

If not him, then who? Of course, you don't take an expert with you to every inspection, but for the house you look at a second and third time because this one is actually being considered for purchase. Who, if not an architect or other expert, can tell you approximately what it might cost? NOT us, not you yourselves. He should also be able to recognize damages that a layperson cannot assess. Besides, not all renovation measures are that simply doable, but why should I repeat myself now? :rolleyes: