You've clearly never used a steam cleaner, because none of what you've described happens, and I use mine on the Cayman. There's not much in the way of steam pressure involved. As for leaning over the fenders of a Cayman, I cover them with large bath towels anytime I'm working in the hatch, like for changing an air filter.And if your using a steam cleaner or pressure washer, (both really bad ideas IMO) more than likely, that's going to be flying right back at you.
Or worse, the interior of your car.
Especially if it's a Cayman.
Picture trying to move a wand around the cramped mid quarters of a Boxster or Cayman engine bay while bent over the back fenders!