I once approved a "minor electrical upgrade" that turned into a full panel replacement, a load calculation audit on three units, and a two-week delay on a lease start.
The tenant was understanding. The budget was not.
That was the last time I let a contractor define "minor." Every scope item in writing now. Every change order requires a signature before work starts. No exceptions.
What's your scope creep story? What did it cost you, and what did it change about how you operate?