You get the price before anything is touched, and the cost of the visit before anyone comes out.
Most appliance repair sites answer the cost question with "call for a quote", which is a way of not answering it. We answer it twice instead: on the phone, before anyone drives out, and again in your kitchen once the fault is known. A published table would be a guess, because the same symptom on two units of the same brand can be a twenty minute adjustment or a control board.
Three things, in this order. Whether the failed part is mechanical or electronic, since a fan motor and a control board are different worlds. Whether the unit is freestanding or built in, because access on a built-in column can take longer than the repair. And whether the part is current or has to be sourced for a discontinued model.
What does not move the number: the day of the week. Sunday is priced the same as Tuesday.