I saw your post and decided to take a look at Black Rose. This sounds very similar to Publish America. I also checked the phone number, 210 232-1935. It’s in the FAQ section. It’s a cell phone in San Antonio, TX. (I used a reverse directory.) I’m not saying they won’t publish or that there’s anything in particular wrong here, but I’ve never heard of an author paying for their cover art.
I got sucked in by Publish America before there was anything bad out there about them. They do publish. They do have your book available to be ordered in any book store, Amazon, B&N, whatever. But using that credit got me stonewalled to a point where I gave up submitting for a few years.
On your point about them editing for free; all publishers assign an editor. No reputable publisher charges for that.