Darnell, Dorrance is a vanity publisher of sorts. I went and checked out the site myself.
--- Self publishing is divided a few ways 1) is you pay to have them print you up a specified number of copies that you sell on your own. 2) Print on demand service. You order and pay for a select number of copies up front and then any other copies made are done upon order. 3) Subsidiary publishing is a service where they print up your book and provide you with as many of the 'services' of a real publisher such as editing, cover art, some marketing, some advertising, however for all these 'services' you pay that in the fee they quoted in the contract. In addition they offer book club, paperback, hardback reprint, paperback reprint, serial reprint, dramatic, motion picture, television, radio, translation, and other such rights on your behalf and will sign a contract for you as an agent of sorts meaning you will only get a percentage of that.
--- A traditional publisher offers you an advance against royalties even before your book is published. You sign a contract they give you half your advance upon completion of edits you recieve the rest. Once you make back your advance you begin getting paid profits from your royalties normally around 3 - 10% for first time authors depending on the genre and length of your work.
What I'm saying is that anyone you pay is a vanity or self publisher of one form or another. It's great they are willing to work with you but if your writing is good enough it should work for you and pay for itself.