Is purchasing a house and complete renovation affordable?

On the topic of heating, I have someone in my extended family who owns such a company and certainly wouldn't squeeze me for every last euro

It also always depends on whom you ask. For our house, we didn’t ask anyone; something like 250,000 upwards would probably have been mentioned (2017). Because many simply need too much luxury and are used to it and consider it normal. The vast majority would definitely have built expensively. We can live with a 15m2 living room. Sure, it could be a bit bigger, but it doesn’t have to be. Our main bathroom is less than 5m2. Many would consider that unacceptable. And it goes like this throughout, and suddenly it’s no longer 200,000 but 400,000.

Friendship ends when money is involved, that’s how it is. However, when it comes to a heating system or a roof, I would avoid "under the table" payments. You have no warranty claims if something goes wrong. The craftsman won’t be able to remember that he spent 2 or 3 weekends climbing around on your roof with you.

Besides that, you still have to finance it, right? The bank usually wants to see an invoice for the disbursement of the costs for the roof, the heating, etc.