Working with a web designer is a long-term relationship.
As technology and trends change, you want to catch-up or add features without having to pay for a new web site's.
Make sure that your web developer:
Offers you the ability to update the web site content YOURSELF.
Optimizes your site for Search Engines so more people can find it.
Understands your business needs and open to suggestions.
Keeps up with the latest technologies so new features may be added in the future as needed
Has good and prompt support. Smaller companies often provide you with better service.