It is a decision based on the plans and directions you have established for your business and the products or services it offers. Originally, businesses only offered their services or products to people in the local neighborhood or community and word of mouth was all that was required. Each of the ways noted above is used to advertise your business at different levels. The Business Cards, Brochures and Company Profile Packets are used to reach individuals. The Ads are used to reach anywhere from your local community to the world community depending where you place the Ads.
Web Sites are the next generation of advertising.
As with all things the answer to that question depends on what you want. Many developers charge additional fees for features like links, forms, number of graphics and image maps. However, Sigma 4 imposes no limits or charges any hidden fees.