I went with Lulu to publish the paper copies of my novels (1 so far with more to come) for several reasons. First and foremost, I was looking for a self-publisher that didn't seem to want to rip me off. It's buyer beware when it comes to printing people's stuff. Flip through the back pages of Writer's Digest and you'll see a lot of ads for self-publishing companies.
Lulu was the one I found that earned my trust very quickly. For one, they don't charge upfront fees. There's no setup fee at all. They make money when the author makes money, period. If someone, like me, feels comfortable with the tasks needed: writing (the big one), editing, proofreading, cover layout and design, cover copy, etc., they can do it themselves and Lulu won't say a peep. They offer a' la carte services for a fee, but you don't have to use them. They don't nag you with emails, or ads, or testimonials. They provide a free ISBN number, which by nature of its use makes Lulu the publisher, but that's no big deal. I read the fine print. They use their number, and will deduct taxes from your royalties like any other publisher, but the author retains all rights. If I decide at some point in time that I don't want Lulu to be the publisher, then I pull the book and get my own ISBN. Lulu, in turn, lists my work with Amazon, Bowkers, and several other cataloging companies that booksellers look to for books.
Most of the markup (and I count anything that doesn't go into my pocket as markup) is Lulu's printing cost, and profit margin...just like any regular publisher has to do.
They're pretty smart, those people at Lulu, when it comes to protecting our mutual interest. They let me buy my books at cost. In fact, they're forcing me to buy one copy of each...hardcover and softcover, before they'll ship a single copy to anyone. That's not so they guarantee one sale, although it does. I'm sure they're covering themselves. If I have to buy one print copy and approve it before they start printing it on demand, I can't attack them if I don't like the way it looks.
So... My apologies to anyone who orders a copy of Sexton before my hard copy arrives... I can assure you I'll approve it as fast as I can so my publisher, Lulu, can ship your copy to you.