Eric Holter makes a great analogy to that of buying a car. "It's possible to buy a decent used car for under $5,000 that should be perfectly adequate to get you where you need to go. Similarly, buying a new car can run the gamut from a bare bones Kia Rio for under $10,000 to a high end Porsche 911 for $80,000 plus. Beyond the desired car's look and style, there are many other considerations that will affect its cost like how many people fit in, how fast it goes, what options are included, etc."
To paraphrase Eric, the following aspects all have an influence on the end cost:
- Visual design (what are the look and feel requirements and how much graphic design will be involved?)
- Site size (how many pages will the site contain?)
- Functionality (search engine, databases, galleries, forms, shopping cart, etc.)
- Project scope (what type of information will the site pages contain?)
- Custom pieces (will there be the need for programming special new features specifically for this project?)
- Development timetable (what is the site's expected launch date?)