Here are some things to think about when choosing a web designer.
This is very important. Take a look at the designer's portfolio. Do you like the way their previous sites look? Designers develop a set of techniques for building websites and tend to reuse what they think works. The look of a designerís websites may differ, but the underlying techniques are usually the same. If you like their past work, chances are, you'll like the work they do for you.
You probably know, you get what you pay for. This is no different with web designers. The better the designer, the more they charge. My recommendation is, don't skimp on web design just to save a buck. Your website will more than likely make back the money you spent on it (directly or indirectly). With that in mind, just because your nephew can make you a website for free, doesn't mean it is necessarily a good idea. Another thing to remember is web designers go out of business all the time. Not because they charge too much, but because they don't charge enough. A reasonable rate ensures that a designer will be around to help you in the future, which is good because a website is just like proprietary software--the person who wrote it is the best person to make changes to it.
If a web designer doesn't give you information about previous clients, turn around and walk away. If you can't find the designer's previous work or ways to get in contact with previous clients, then chances are the designer is trying to hide something--Possibly the fact that they provide poor customer service. Look for testimonials or some kind of proof that previous clients are happy with the designer's services.