2006 Jaguar XKR warranty

The factory warranty on my '06 XKR convertible will expire around the end of the year. The dealer will sell me an extended warranty for approx $3500. It will cover for 3 years and up to 100,000 miles. My garage queen has 17k miles now, is stored during the winter months and will not come close to reaching the 100k miles. Does it make sense to buy the warranty? Also, if I take the car into the dealer prior to the factory warranty expiring, can I have them go through the car to see what could be done on the factory's dime and what should they be looking at that might be costly down the road that could be worked on now?