If there are obvious errors in the calculation (financing/ construction costs), one should address them!
Yes, but the question is how, and then you can also point something out instead of just throwing something out there wholesale, and above all, one could also ask whether the original poster is even interested in that! Everyone can write whatever they want, even unsolicited as far as I'm concerned, but the question must be asked, it must be allowed, on what basis one makes a blanket statement.
What, for example, do you have to criticize about the costs in this thread and on what basis would you justify your opinion?