Exactly, we actually know far too little about the house. A whole paragraph is dedicated only to the cistern. It is not insulated and the heating system needs to be replaced for 10k€ (aside from the fact that a new heating system including hot water for 2 units at that price, even with equity, is ambitious). What about the roof? Original condition? If it needs to be insulated, the thousands will pile up quickly. Even if you know many craftsmen, so BAT, quite a bit will be spent. Oh yeah, and it doesn't have a kitchen, or rather 2. I am more with Nordanney who categorizes it closer to a better shell (I didn’t want to say a dump). With a 4 kW storage battery of that size, you won't get much of anything, I always think about the additional costs and those won’t be small at that size... Speaking of which: energy certificate?