Leigh Thomas Brown teaches a negotiation trick: ask "Do I have your permission to tell you the truth?" before delivering hard feedback. If they say no, leave. If yes, you can praise honestly and suggest improvements without triggering defensiveness, then frame offers with market data and conditional outcomes.
the other side, do I have your permission to tell you the truth? You also have to shut up after you ask that question. That's a different skill for a different day. But I want you to remember that when they give you permission, because they will— and by the way, if anybody says no, you don't have permission to tell me the truth, you should walk away, wash your hands right then, because that's never going to work out if you don't have permission to tell the truth. So now, once they've said yes, you can tell me the truth, What I'm going to be able to do later is say, your house is wonderful and we have an opportunity to improve it if we pull the wallpaper and paint it. We have an opportunity to present this in a better way if we do X, Y, and Z. With that buyer, you can say, yes, I'm glad you like this house. And if we make an offer of X, Y, or Z, I can defend that with market data. And if we make an offer that's lower than that, it's harder for me to defend it. However, there are possible outcomes. When you start talking to people about the possible outcomes of if this, then that, just like they do in coding world, or Plan A versus Plan B, or the classic Ben Franklin pros versus cons list, you'll find you have a different relationship and it won't be so contentious.
