As a data point, I've just booked the AF Meet and Greet Transit service at CDG (T2E to T2G) for a one-way flight in May. Although it took AF 5 days to make contact, I was charged 200 Euro for the service for one passenger. I'll report back on the experience.

For information, I also contacted Extime and they quoted 342 Euro for their meet and greet transit service, admittedly this was for up to 3 passengers. I also enquired about a car transit and this was quoted as an extra 280 Euro (for up to 3 passengers), but they were very vague whether this was an airside or landside car transfer.