Should I put my client's interests ahead of my commission?

You already know the answer, or you would not be asking. The pull is real. A bigger deal means a bigger check, and there is always a way to nudge someone toward it. But you feel the cost of that nudge, and that feeling is worth listening to. Think about time. A commission is one payment. Trust is a stream. The client who feels you protected them tells three others, and those others tell more. The person who feels used tells everyone too, and louder. Serving their true interest is not just right, it is the longer, wiser bet on your own name. When the two pull against each other, pause and ask one plain question. What would I advise if there were no money in it for me? Say that answer out loud to them. You will lose a few deals and keep your character, and in this work your character is the deal.