My business has two sides: a workshop that builds props and merchandise for magicians and entertainers, and a regional shop where things are personalised while the customer stands next to you. Both live off the same machines.
That is why I know the questions a brochure never covers. How loud is the machine when someone is shopping in the room? How long does the change from wood to stainless steel really take? What happens when the file is badly prepared and the customer is back in ten minutes?
At a demo appointment you get answers from the shop floor, including the cases where the answer is: do not buy the machine yet.