Checkin time is pretty much the same as your outward flight - 3-4 hours before takeoff. It really depends on how long you want to spend at the airport and how much time you want to give yourselves to get to the airport - allowing for traffic etc.
Tiffany will pick you up at what ever time you tell them to
We used Tiffany last year and we told the driver when he dropped us off at our resort what time to pick us up and then we also rang to confirm on the morning of our departure (just to be sure

).