I had a situation where a client was asking me to retile an exterior patio that was showing signs of water damage in the stucco below. I told the clients "we can definitely take this tile off but there won't be turning back once we do. If there are problems with the patio, we'll have to address them and it could be a lot more expensive." Then the worst case did in fact happen, was my biggest change order I've ever issued and they were totally fine with it.
That's a great example of why honest communication upfront is so important. You didn't promise what you couldn't control, you prepared the client for the possibilities. When people know what to expect, even difficult conversations become much easier
