Try this (can't remember where I got it, but it may help) :I would also like a definitive list from Porsche to review.
key elements called for at 20K are oil and filter change, pollen and air filters and brake fluid flush, plus a bunch of checks/adjustments. Note that when I asked my dealer for a price for the 20K service I asked if it included the brake flush. He said no, that Porsche requires that to be quoted separately even though it is clearly called for in the maintenance schedule. So be sure to ask your dealer about this when getting a quote.The major tasks are an oil change and brake system flush and refill. And checking 30 other things.