A true Publisher pays the author for their work.
If you are asked to pay anything then you are dealing with a print broker. The best of these offer editorial and design skills as well as guidance on marketing and distribution BUT THEY ARE NOT A PUBLISHER. See below for a link to more information.
The only exception is where some small Publishers will negotiate a sharing of the risk facility. Get advice before proceeding.
dahlDESIGN's manuscript assessment service can not guarantee you will be published.