Most utility contractor problems trace back to something that could have been clarified in the first conversation, not the actual fieldwork.
Are you licensed and insured for this specific type of work?
Do you call 811 before every dig, without exception?
What happens if you hit an unexpected utility or obstruction?
Is site restoration included in the quote, or billed separately?
Should restoration always be included in the quote?
Not always, but it should always be clearly stated one way or the other before you sign.
Is a written scope of work necessary for small projects?
Yes, even small jobs benefit from a written scope to avoid disagreements about what was actually included.
A contractor who answers these questions clearly and specifically is telling you a lot about how the actual project will go.