@Mame,
If he's paying for things like the ISBN, editing, cover art, and everything involved with uploading, then it's probably self-publishing. But be aware that there are scam artists out there (including vanity presses) which require authors to buy all that and more.
With traditional, legitimate publishing, the money only flows from the publisher to the writer, and never in the other direction.
So, he is
probably self-published.
There's a lot involved with publishing a book-- it's not a cheap hobby. It's also where you have to wear a lot of hats--marketer, accountant, publicist, and Amazon liaison, among others. Very time consuming. And you're also supposed to be writing, self-editing (before it goes to the pro editor), coming up with new ideas, supporting your fellow authors, making contacts, attending events and selling books there, and giving book talks at local libraries.
Now imagine all that with children, or a full-time job, or being a caregiver, or having a chronic illness, or depression, or a disability. Or some combination thereof.
The price may or may not be realistic. My own novel is still priced at, IIRC, $19.95-- with the e-version priced the same.
I honestly believe that the publisher I went with is okay but they had no idea how to market or price a science fiction book by an unknown author.
The same may be true of this guy, that he's being unrealistic about pricing.