Code - Database Review

I just had someone code a internet application for me. I am thinking it would be a good idea to have someone else do a code/database review.

Things I am looking for include:

  1. Security issues
  2. Design issues
  3. Performance Issues
  4. Load issues
  5. Best practices and code documentation

How is this done? Do I simply contact another “programmer” to do the review or is there a special skill set that is needed.

Thank you so much.