Covercraft does the job
I mainly wanted some kind of cover for my cargo area because I have dogs for passengers. The Covercraft Cargo Area Liner fits nicely and provides a barrier between dog hair and the vehicle's carpet, which would draw the dog hair like a magnet. The Covercraft liner is not heavy duty, but it is thick and tough enough to do the job. It would be nice if I could throw it in the washing machine, but it will be easy enough to clean it as they suggest: brush with Simple Green and rinse with hose.
2012 Jeep Liberty Jet covercraft liner
Ordered this to protect my carpet in the cargo area of my Liberty even when the rear seats are lowered flat. It will work great for that and when I have to take my dogs somewhere but for the price I expected it to at least have some type of padding under the protective material and be thicker so things won't puncture it so easily. I purchased a cover for my passenger front seat for pet protection from Marshalls that is the same material and thickness and was only $15.
The seat back liner and the floor liner connect with velcro. There's one strip for when the seats are down and one for when they are up. Moving from one strip to the other when raising or lowering the seat takes a little effort, and mine doesn't look as smooth as the picture when part of the seat is down. But it does the job.