Barnes and Noble publishing cost is two different products: (1) uploading files yourself through B&N’s self-pub tools, and (2) making a title orderable so B&N or similar retailers can carry it if they choose.
DIY B&N / Nook-style rails
If you already have retail-ready files, platform fees are usually low. You still need a cover, interior, ISBN, and metadata. That is the same file problem as KDP.
Bookstore orderability (what packages buy)
AuthorShelf packages include global retail / POD setup so the book can be ordered through wholesale channels where policies allow — including Barnes & Noble pathways for qualifying titles. That is not a paid endcap or a guaranteed store table. Returns (needed for many brick-and-mortar buyers) are included on Pro and above.
Listed AuthorShelf production: $399–$2,989. Compare: how to get your book in bookstores.