Ugh, does that ever make you feel gross when you see it happen? I work in a different trade, but I see that too, where a simple job gets padded with stuff it doesn't need. Being straight with people about what's wrong and what it costs is just the right way to do things. That honesty is how you get customers who actually trust you and come back. It's good to hear someone else aiming for that, it makes a real difference.
Ever notice how that kind of honesty just makes everything smoother? My neighbor, who @holly_jones29 would probably get along with, only calls one guy for any house problem because he's always straight about what's needed. That kind of trust just feels like a solid win for everyone.
Holly_jones29 says being straight about costs is right, but that view misses the full picture. Sometimes jobs have hidden problems that need extra parts, and charging for them upfront keeps the business stable. While @oliviac22's example shows trust from honesty, long-term service often requires a buffer for unseen issues.