Estimate of construction costs for a single-family house in the Tübingen area

Are you ignoring again that what you yourself (or through buddies) can contribute only counts if it also fits into the process of your

No, I think I just repeat myself too often and that creates the impression that I am not listening – I will stop. The house must be occupied from June 2028.

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5. Check bindingly if, what and how much your buddies are willing/able to contribute
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How do you definitely check if the buddies can do that and want to perform over months or years?
Buddy or not, working hard physically together is something completely different. And it is also something completely different whether you do it for yourself or for a buddy.
I've been through that, now I do most of it alone or with 1-2 people I can work well with and who do good work.

I had to sort out the rest because I have to explain too much and/or it’s just slapped together quickly, as long as there’s beer and a kebab after work.

The best way is to assume that you do the work alone in the end, at best with 1-2 helpers who are usually really just laborers, so handing things over, carrying, etc.

Unless you really have craftsmen in your circle of friends, i.e. professionals. But these often don’t have time in the end because they work overtime in summer and can’t do anything in winter.

How do you reliably check if the buddies can do it and want to perform over months or years?

Through communication. Clearly discuss and agree on something together. With reliable people, it is quite simple to find out what is possible, and with others, I wouldn’t even discuss it.

Buddy or not, working hard physically together is something completely different. And it is also completely different whether you do it for yourself or for a buddy.

A buddy is a person and therefore everyone can be different in that regard. That is exactly what it’s about, to find out these things reliably, and if it doesn’t work out, then that is an important and above all necessary insight.

I’ve been through it, now I do most things alone or with 1-2 people with whom I can work well and who do good work. I had to sort out the rest because I have to explain too much and/or it’s just botched quickly, as long as there’s beer and a döner after work.

That is individual, just as people are individual; blanket statements are, as always, not helpful for that. If it was that bad for you, maybe it wasn’t sufficiently clarified by both sides beforehand. I don’t have such buddies or wouldn’t call them that. But there’s also the saying: “Don’t look a gift horse in the mouth...”

The best way is to assume that you will do the work alone in the end, ideally with 1-2 helpers who are usually really just assistants, like handing things or carrying stuff.

That may well apply individually to you, but it is not a general template.

Unless you really have craftsmen in your circle of friends, i.e. professionals. But especially they often have no time in the end because they do overtime in summer and you can’t do anything in winter.

This can also be different. There were craftsmen who helped me a lot, and I helped them in other ways; why should that not work? Everything clearly and reliably discussed beforehand. Just because money is involved in a company assignment doesn’t mean it has to be shoddy without money. The question probably also is how I define friendship or being buddies in general; there may be considerable differences there. It’s as always: Between white and black there are thousands of shades of gray just as there are many things, even though not everyone can imagine them. Clarity from the beginning is important and not hidden expectations.

Through communication. Discussing clearly and agreeing on something together. With reliable people, it’s quite easy to find out what’s possible, and I wouldn’t discuss that with others either. (...)

Your theory already fails in the first paragraph against reality. Who is really reliable and who isn’t doesn’t show in intense conversation... it only shows in reality on the construction site when you’re supposed to help a buddy for the fourth weekend in a row and your wife complains about when you’ll finally do something with the kids again...

But I don’t have to convince anyone here, I’m merely describing my experience, which matches the experiences I see around me. Most builders around me slave away alone, help comes maybe once every 2-3 weeks. He has to decide anyway. But when planning such a project, you should rather assume the worst case where in the end you’re mostly on your own and not the best case where all friends promise help for 2 years.

Hoping is not a good strategy.

Your theory fails at the first paragraph due to reality.

In your reality or with you that may be so. A pity. Apparently, you overlooked that I practiced exactly that in my own construction. I had clear commitments about when, who, and how would help or not; all of these were kept. What was not possible was also not promised, quite simply. Agreements are not only made on construction sites but everywhere in daily life, and reliability or clarity should be an indispensable basis of friendship; at least that is how I see it, but I have no doubt that it is not the same with you.

when you’re supposed to help your buddy for the fourth weekend in a row and your wife complains about when you will do something with the kids again.

Then your friend probably fibbed to you or you didn’t clarify it firmly or both. Whatever it is. We don’t need to speculate further about whether people can make binding agreements among each other. Everyone chooses their own environment and is completely responsible for it themselves.

I am merely describing my experience, which matches the experiences I see around here.

As I said, I have no doubt about your experiences but (see above about personal responsibility in choosing friends)

Most builders around me are grinding alone; help maybe comes every 2-3 weeks.

That may be so, perhaps they simply haven’t arranged anything else or don’t know anyone who helps them. That is clarity too and does not contradict my statement.

He has to decide anyway.

Always – personal responsibility applies here as well!

Hope is not a good tactic.

Hope is the opposite of agreement. Although – if I have a good environment, hope is often rewarded (in addition to agreed help). With such an attitude of “Everyone else is lazy, eating my döner and wanting my beer,” I can do little, because I never had that in my life. I did a lot alone or with my wife but I always got help in various building projects, and especially in emergencies, someone was there. I appreciate that to this day! But even here it is always a give and take, and maybe you also have to look at what you have given or are willing to give yourself in a binding way. There are many ways to Rome here too.

In your reality or for you that may be the case. A pity. Apparently you overlooked that I practiced exactly the same during my construction. I had clear commitments on when, with whom, and how help would be given or not; all of these were kept. What was not possible was simply not promised. (...)

What would have been your lever if someone had not kept their commitment? Maybe we live in different worlds, which would not be reprehensible. In my world, two buddies switched jobs abroad in the past two years; they couldn’t have fulfilled the "BroCode" anymore, even if they had wanted to. Just because it worked out for you right now, you can’t seriously recommend that across the board to everyone? How naive or forgetful is that? Be glad it worked out that way for you; in 95% of all cases it goes differently.