Experiences with construction cost savings through self-performance?

If the standard equipment from the factory is cheaper than outsourcing with the same objects, then it doesn't make sense. If I can get it cheaper, I can invest it in a higher specification or even in the outdoor facilities and so on.

Both should be relatively equal, because either the home builder makes money or the downstream craftsman you hire. However, you can have bad luck and end up building more expensively or vice versa. But you definitely have more work and more contact persons – also for defects and warranty issues.

The options are intended for DIY and/or craftsmen in the family and circle of friends. Not to replace one professional with another.

we have inquired with some consultants and building surveyors. So far, only one appointment has been made, but we did not find the conversation likeable. The others currently have no interest or are already fully booked. There was also simply no feedback at all.

You are welcome to contact me. I am not an "expert" offering construction management and quality controls myself, but I can gladly find such people. As far as the construction is concerned with a "prefab" house, I have already named the recommended colleagues; in the "solid" house sector I can find some for you.

We continue from this point. Nevertheless, we have also further dealt with the subject of "model houses."
This is a model house that we viewed exactly as it is pictured or existing (it was currently under construction for another building family).
We liked it. Therefore, this offer came up now after we exchanged information with the manufacturer’s consultant.

Is this "other building family’s" house a model house / promotion house?
I am also happy to show you how to conduct a kind of "tender" with the goal of receiving an offer for a model house.

good assessment. We would see ourselves the same way.
And that was exactly the point for me as well.
Ultimately, I would award everything for the "ready for technology" points (except for pulling cables and drywall with thermal insulation).

By "drywall with thermal insulation" you probably mean installing the insulation panels and plastering the raw finished walls? – erecting drywall partitions actually requires a little more craftsmanship. During the basic installation, quite a bit is already inside the walls, except for the switch and socket positions which are arranged after consultation.

If the standard factory equipment is cheaper instead of subcontracting with the same objects, then it makes no sense. If I come out cheaper, I can invest it in a higher specification or even in the outdoor area and so on.

I just cannot assess the quoted prices, whether the provider’s prices are exaggerated and the same quality could be 50% cheaper on the market, or if it’s fair and then it is better to pay the surcharge for everything from one source.

General contractors including the "house manufacturers" are usually masons and concrete workers or carpenters who need subcontractors as further team members and never procure them with less skill than the builder himself. Just replacing Heinz with Willi does not make anything cheaper here. You can really save when customizing, changing, and removing mainly where, for example, the general contractor’s tile dealer does not offer products differing from your quality requests, but only differs from you purely in taste (otherwise you would pay a lot to the GC just to get "the same in green" in a different green than exactly their green). Also, builders with automation wishes know this game when the religious convictions between builder and GC differ on the level of bus systems for Alexa, Siri, and Cortana and in this sense "outside there are only kettles."

Is this "other building family" a type house / promotional house?

Yes, it was exactly that house because it is a promotional house. Except maybe different windows. In terms of equipment, maybe finished differently than we would choose. But otherwise, the layout and all the rooms are identical. So we just had a good overview of room size, paths, floor spaces, light, etc.

By "drywall with thermal insulation" you probably mean inserting the insulation boards and cladding the raw finished walls? - erecting drywall partitions requires about half a level more craftsmanship. With the basic installation, quite a bit is already inside the wall, except for switch and socket positions after consultation.

I have already erected a drywall once, but this is already included at the semi-finished house stage. I would have this done. Cladding should then be relatively easy. Since the walls should be absolutely straight (new build), this is not a big undertaking. With an old building with crooked walls it was a completely different matter and took a lot of time.

"Technically ready" also means the electrical installation is done, and heating, water, etc. are running.

Bathrooms are also planned, they just need to be tiled and equipped with fixtures.

what is doable (yes, I don’t have two left hands, but of course I would have to acquire knowledge).

I think that if, as you wrote further below, you will not do the technology and so yourself, but will hand it over to other craftsmen, it is more a matter of time or a time question. How much time can you/can you all invest to complete the outstanding services?

I think for the equipment offered above you won’t get cheaper with subcontracting, rather it will probably feel more expensive.

I think so too. The home builder takes the surcharge for his profit, the independent takes the surcharge for the “I come when you need me.”

possibly find out what it costs for samples.

While reading I thought there is room for improvement everywhere, namely upgrading with samples.

Well, you do have relatively modest wishes. So I don’t necessarily see solid oak planks instead of finger-jointed beech wood or the very expensive and oversized tiles.
However, a socket package as well as this and that will be needed.

If you take "almost finished," then the work remaining for you is

- Filling work on walls and ceilings
- Wallpapering and painting
- Doors
- Floor coverings

Later then the exterior work..

That can easily take a quarter of a year if you do it as two people alongside work and vacation.
Possibly a break to give your back a rest..

Phew. Complete interior construction including filling, sanding, painting, doors, floors properly executed alongside work in 3 months as a non-craftsman? So without being used to the movements and generally quite physically demanding work? Very ambitious plan.

Regarding your actual question:

I find the listing rather favorable. If it’s about the price, I wouldn’t assign it myself.