publishing - Can a literary agent be hired?

I've sent my manuscript to tens of literary agents. Strangely enough, I received no positive response.

My question: Can I hire a literary agent? If yes, how much it costs?

Are there other ways (except of vanity presses) to publish and widely distribute my religious book?

I may probably get a grant for publishing this book (instead of my own expenses). But I don't even know how much to ask, because I don't know how much I need to pay for publishing.