The prices you list seem about right--if you are searching for editing on line.
My searches for other editing suggest that these prices might apply in professional editing across the board if you are an author seeking editing.
I'm fairly certain that publishers get a much better rate.
Acquiring editing services is a double edge sword and it is best approached as @Brian G Turner
suggests--search for an editor who will edit a portion for free so you can see if they are a good fit and see if they do well. However remember that you are the one judging how well they do and the reason you are not doing this yourself is that you know you don't have everything it takes to do this yourself. That's the double edged sword.
That much said, just having grammar and spelling and punctuation checked can be quite costly and possibly in the thousands for such a bulky manuscript. That was the problem with mine and one reason I went with Xlibris POD; they have their own editors. And once again the problem with this is that you still don't know what you are getting. They did a fine job of finding a multitude of problems and helping fix them; however there were far too many things that both they and I missed that I'm still sorting through.
The cheapest editing is, do it yourself, which is insane to even consider. But this is one reason that the eBook self publishing industry is where it is at presently.
My advice is search out students from nearby universities and seek out beta readers for help and suggestions. They still do not replace a professional edit that includes Substantive, content, continuity and structure, which is what gets really expensive and even with a POD publisher you can get a massive bill for those services and not be sure what you will get until you get it.
One thing to remember is that if you have in depth editing that will require a rewrite that then needs editing again--Who will do that and how much will it cost--Even the POD publishers have a limit on how many passes they will allow in editing before you have to pay once more.
It would be interesting to have some of the editors in this forum come up with a price list for services.
However it should be noted that often editing services have a caveat that they need to read a chunk of your work before they can truthfully quote your work; because some writers will need much more editing than others and this is why there is an emphasis on trying to get as much of the grammar, spelling and punctuation correct before sending it out for edits.
One last thought: I know of no editor who can guarantee that your novel will sell well after they edit it. In essence the only person guaranteed to make good money from your novel is the editor. So choose wisely.
Here is an interesting chart I ran across-took a while to re-find it.
Editorial Rates – Editorial Freelancers Association
First part gives a pace to price chart for services relevant to conversation.