Cost planning - core renovation of farmhouse / country house

Hello community!

Freely following the motto "a house is not a house," I am mentally still not quite done with the future planning of living arrangements.

A mix of various factors (the provocative neighbor is only ONE of 6-7, please ignore him thematically this time) has caused us to currently look a bit at existing properties. The consideration is initially hypothetical, more concrete possibly mid-2022.

We would like an old farmhouse / rural estate in a solitary location, ideally with outbuildings, and are looking for something that has not yet been extensively renovated, but is cheap because we want to gut renovate. Offers here in the area for properties that suit our plans are possibly between 200-300 thousand euros.
Broker fees usually apply as well (luckily sometimes not, but I would rather include it), and of course the incidental purchase costs.

I am not a construction specialist, except for the first building I followed along with. I naively imagine that one basically “empties” the old building down to shell level. I would like everything new, including all plumbing for water and electricity.
What costs should be calculated (per square meter, roughly?) to strip a house down to shell level?

Afterwards, I would like the amenities I am used to here again, meaning: air-water heat pump, underfloor heating, central ventilation system, air conditioning, photovoltaic system, new windows, insulation standard at current level (we have KFW55).
How can I approach the numbers on what such things cost? Are there general contractors who also do gut renovations or do they specialize purely in new builds?

In my head, a rough figure of 200-300k is floating around for the gutting and renovation, so that the total project costs would be approximately 600k. Is that unrealistic or possibly doable?

Utopian. If you really want to buy a farmstead that has not experienced any significant renovations in the last 20 years, then you can - without considerable personal effort - expect new construction costs plus about 20%.

I just looked at the costs for a project overseen by our office, where a farmstead was renovated to new construction standards. Basement, 2 full floors, attic. 280 sqm usable space. Three bathrooms, basement renovation, attic conversion, wall heating, all surfaces new, new roof, new windows, underfloor heating, ceiling cooling, new kitchen. Everything at a high standard, but nothing completely crazy: 1.2 million. Of that, about 140,000 are pure planning costs.

Afterwards, I would like to have again the amenities I am used to here, meaning: air-water heat pump, underfloor heating, central ventilation system, air conditioning, photovoltaic system, new windows, insulation standard at current level (we have KFW55).

This will be an exciting task. As long as you don’t have to consider monument protection, it is also relatively easy to implement.

How can I approach the cost figures for something like this?

In total, take the new construction prices. So just calculate with €2,500/sqm. But depending on the situation, it can be somewhat more expensive, especially if you aim for KFW 55 or a central ventilation system (insulation in the floor without basement = excavation / central ventilation system means that somewhere the ceiling has to be lowered at 220 cm ceiling height or an upper floor is needed where the pipes can be laid, etc.)

Are there general contractors who also take on full renovations or do they specialize purely in new buildings?

For the general contractor it basically does not matter what they build.

I have an estimated figure of 200-300k in mind for the gutting and renovation.

That works for a small 100 sqm house, but not for a farmstead. Around here I know them always from 150/180 sqm upwards. Renovated (not in the condition you mentioned) you quickly get sales prices of €600-750k, fully renovated usually always in the direction of €1 million +X. Location: In the countryside with negligible land prices...

Sign at , we once had an idea like that too. According to my research, only sensible if a lot of personal effort is possible/wanted, otherwise hardly affordable.

There are specialized companies for renovations and conversions. With the amenities you mentioned, you will never manage. Although I live in [bw] and not in [NS]. But with windows, roof, and without photovoltaics and electrical work, but with the things you mentioned, the offer was significantly higher. That is why we are now providing significantly more electricity.

Such projects only work if
a) you can live with a lower standard
b) you can contribute a lot of real construction work yourself and have good local connections to all trades
c) you are RICH.