Self publishing is a bitch. It really is. You need to handle all of these tiny little details, and the details are hard. So, of course, people have stepped up to fill in the gaps.
There are packages you can buy which promise to handle all of the details. These packages will include cover art, distribution, printing, editing, etc.
These packages are not cheap, not even a little. You are paying thousands of dollars by the time all is said and done. Of course there is no other option, all of the things involved cost money. If you can’t do them yourself, either due to time or due to lack of ability, you need to pay to have them done. Editing in particular is a bitch to do yourself, because you won’t see your own mistakes.
I can do cover art, sort of, and I did it for my first book. I like it, but I don’t exactly have high sales volume to back that up.
So, these self publishing options exist, and many are legit. They do the work, they make a few bucks, you don’t have to handle the details. Of course that isn’t all of them. There are other ones that charge a huge fee, massive markup, and offer minimal services. They are straight up scams.
How do you tell which is which?
First look for comments online. Preditors and Editors is a decent resource. They review self-publishing companies, as well as editors and the like.
Look for promises. A self publishing company provides some basic services, they don’t promis you the moon. If a company is charging you money and claiming they will make you a multi-millionaire author, they are probably full of it.
See if the company has a list of authors they have worked with, try to get in touch with some of those authors.
Basically, be smart and do some research. Don’t take these places at face value.