How do you ensure you get a good contractor beyond asking for references? Spending extra money is not a guarantee.

How do you ensure you get a good contractor beyond asking for references? Spending extra money is not a guarantee.

We went through end of the roll to get new flooring and used their contractor. Overall it looks ok but the finish is not what I expect from a professional. Glue was used on a no glue flooring and, with no premeasuring, there are little strips or triangles of fill in pieces rather than actual planned pieces. Sure the floor is warranteed but we would have to remove the baseboards again to get it done. When we hire professionals we expect that last 5% of the work to be as good as the easiest 80% of the job.
https://www.cbc.ca/amp/1.4860208