I work with 125+ lender partners who are competing for my business as well as yours. I can almost always find a lender who will pay my entire fee! If for some reason they won't and you really like that specific lender's terms, it may make sense for you to pay my fee—but I would have a conversation with you before that would happen.
My application is completely free! That said, I do encourage you to purchase your credit report as the first step in the process, since I need a credit report to give you an accurate quote or pre-qualification letter. Right now that fee is $99, which goes entirely to a third party.
If anyone else does not ask you to purchase your credit report, they are usually buying it for you temporarily and charging you back at the closing table—and they can't even give you a copy by law. Pulling your credit first allows you to have your own copy to review as you begin your home buying process.