Normally, if you want to have professional designers custom build your site, you must be prepared to dish out at least a few hundred dollars. All this can change if you know where to find the best deals, the best designs for the lowest price. Here's a rough guide:
First, you must understand that it is a rip off to get companies to design websites for you. Have you ever seen those advertisements in newspaper classified ad sections that offer a 5-page website at $500? These companies are established companies with physical locations, therefore they have to increase the amount they charge to pay off some overheads: office rent, designer's wages, advertising costs and so on.
Therefore, it would be wise to find freelance designers who work from home. These people are often working from home so they do not have a high operation cost like that of a company. On the other hand, they will be able to design images with quality similar to those of designers from big companies, so it's a "no-brainer" choice.
Another route you can take is to design your website yourself. Think about it, if you only need 5 simple pages to present some simple information, why waste hundreds of dollars for it? Just spend a little time to sit down and do it yourself. You'll be able to design your own sites even if you do not know a single line of HTML code with the help of WYSIWYG (what you see is what you get) programs such as Microsoft Frontpage, Macromedia Dreamweaver and so on.