here is my cliff notes, avoid having one key fob at all costs because if you lose it or it breaks..........it takes awhile to get a key, your car is stranded, and immobilizer mode is annoying, makes towing difficult, and just spend the $400 like an insurance policy before what happens too me...

Update on Process.......

Necessary Items
1. Key Fob for my Cayenne 2006 Base is a 315 mghz 3 button key Fob(187 @ ECS, bought a cheapo on Ebay for 38 bucks)....most any locksmith can laser cut it for (20-50 dollars), dealer program (75 bucks).
2. The actual car needs to be at the dealer as well @ program time, so if you are on emergency basis of needing a key, you will need to have it towed....I found out the hard way and had to do a 2 hour run around to get the PIG towed.
3. Have the key overnighted if you are in an emergency situation, as a rental and wait can really hold you up.
4. The dealer fully cut/programmed key is not too bad @ $400-300 if you are paying overnight, rental car, and towing fees if you do not have premium service.
5. Love having a fully functional key and will get a 2nd soon.