I've coached a few people. One person hired me to go over a business idea. I came up with obstacles she never thought of. As a result she paid me a couple of hundred bucks and folded up her tent. Had she gone ahead with her idea she would have lost her shirt (imho).
Coaches can be an asset, if they have the right credentials. Beware of the types who tell you what you want to hear instead of what you should be told. Your best interest should be their best interest.
Get a mentor instead that has been in business and was/is successful. You think a person doing business coaching has the right credentials, if they were so good they would be running their own businesses.