I ensured my car was wash sufficiently enough to remove all grit etc, on the outside of my car so my dealers 'scratch & vac' didn't damage the finish of my paint work if they decided to do it without my knowledge. Also it will be a very good plan to insist you don't want a Cabin Refresher as it absolutely stinks.
In regard to the time it takes, my dealer told me it would take longer for my 2nd Service as I had a Courtesy Car and as a rule they will take longer to do cars where the customer has a courtesy car. So if you are in a rush and want your car back sooner don't get a courtesy car.