When you hire a professional web developer to make a website for you, it is also going to cost way more money. There are low-priced developers, and then there are high-priced developers. But no matter what you are going to end up paying way more than what you expect. Each one comes with pros and cons. Low-priced website designers are not going to be that experienced, but that is why their prices are going to be so low. This does not mean that they do not have the skills; they just are not proven enough yet to warrant a high price.
CMS helps to separate design of web site from its content. It means designer develops a web site and gives it to its owner or manager who can fill a certain design with different content. If necessary the content of web site, its images and graphics can be easily edited without intervention into design of web site. All changes become visible as soon as you make them. (Don‘t forget to reload page after making changes). Even if you are not an expert of HTML coding, you can easily manage the content of your web site yourself.