The interior is very versatile and can be configured to carry cargo in different ways.
If longer room is needed, you can pull the front passenger seat up, remove the headrest, and recline the seat all the way to match up flat with the botom of the rear seat. That gives you a 6 foot flat bed the width of the passenger seat down that side of the car.
Folding down the rear seat, you can lean the front passenger seat forward and use that side of the car all the way up. Depending on the size of the item carried I've been known to have a passenger sit in the rear seat behind the driver instead of the passenger seat so I can use that long side of the car for large cargo.
If you need the rear section to fold flat with the rear seats, there is a cargo organizer available through Nissan that is designed to do that.
http://www.courtesyparts.com/n..._7638