reject any contractor who says they never had a complaint.
best of contractors find themselves in disputes for one reason
Ask the contractor
for the name of a problem account and explanation as to how they
rectified the complaint.
Be forewarned that
many quality contractors, in business for a long period of time,
and with thousands of completed projects, are exposed to disputes.
The question is not if they have had disputes, but what was done
about the dispute after it occurred.