E-commerce sites are much more expensive than a normal website for the following reasons.
1. Each product that is sold has an image, a description, price, weight and dimensions. They can also have variations, such as size, colour, etc. This is data entry and you can save money by entering in the products yourself.
Many of our clients have opted for this and we have made it easier for them by supplying all product images to them in the right size and format. Then its just a matter of copying from one product to the next. Naturally, the more products you sell, the more expensive the website.
2. E-commerce sites are much more time consuming to set up. There is shipping to add and configure, payment gateways, and the configuring of the platform that is used to sell.
3. Much planning should go into the development of an E-commerce site to provide end users with an easy to use and enjoyable shopping experience.
4. SEO should also be deployed at the beginning of the development of an E-commerce website, as there is not much point having a great website if nobody can find it.