As in most things in the normal world, the QUALITY of workmanship is what dominantly affects the final price of the site.
We will try to explain to you in a few sentences, in essence, the complexity of creating a site and everything that affects the quality and thus the price of the final product, in this case the site.
So the site can be the most common front panel image with the assigned web address and domain on a particular hosting. Of course, this is not what people who expect positive changes in business from the site need.
In this regard, for the simplest sites or, say, another category of what is called a site, it is necessary to do a few pages of the site in a platform (Magento, WordPress, etc.). Here we come to the basics. The site can be written-coded (which is the most expensive creation that takes a very long time and affects the uniqueness of course) or you can use so-called tools with themes that allow the same purpose but dramatically save time and of course do not affect the functionality of the site.
The next segment that is very often the most important is SEO Site Optimization, without the implementation of which the site is not visible to search engines. The whole area of optimization, which is of course primary and secondary, includes first of all choosing keywords, setting up the site on the GOOGLE search engine platform and opening the site from different IP addresses, which requires your help.
The possibility of upgrading the site itself is predominantly important for the future, all in the hope that the function of the site has hit the target and that the business is developing and will develop more and more.