What value do the advisors really bring and why should I hire one?

They will give you a second opinion about your intended sale even before embarking on a sale journey.
They will challenge your expected price tag, help you understand if it should be higher or lower and outline the road to maximize your target price.
They will bring you a competing acquirer that will drive the value of your company higher in the negotiation process.
They will help you focus on what you do best – continue creating value – while help negotiating the best deal with your acquirer. That in turn reduces the time and the stress involved in the sale process.