After having my pool refinished; and haveing many problems with it, here are my new 2 rules for hiring any contractor:

1. Anytime they have workers on site, someone must be there who speaks English; fluently.

2. They must accept credit cards (Visa, etc). If they are check or cash only, then you are out of luck if you want them to come back to fix something and they refuse - legal action then becomes your only option. With a credit card, at least you can dispute it with card co.

3. The get their final payment after completion (and then a few days). Most pool cos. down here want their final payment BEFORE they start final plastering.

If these are unacceptable, then they don't get the job.
Lesson learned the hard way.