I designed the Prius to sleep by removing the back seats and replacing them with multi-hinged plywood that would form a bed platform that would give me 6 foot 2 inches of bed space behind the passenger seat to the rear hatch.
This space would accommodate me at 5 foot 11 inches and the mattress and sleeping bag.
I chose this design over others involving folding the front passenger seat forward as it gave me a truely flat surface and although the front passenger seat was pushed nearly all the way forward. The back of the seat was at the center post and this allowed me to run a curtain across the back of the seats and when I stealthier in parking lots it looked like the vehicle was just parked as the front seats didn't look odd in that position.
At night I could also lean my back on the back of the front passenger seat and this semi reclined position basically gave me another position of comfort vs only laying down.
Being able to fully recline was important for me along with having a full-size sleeping bag. This gave me ability to move around and change positions for variety of comfort.
I had a homemade sleeping bag liner made from a full-size flannel bedsheet that was folded in half and sewn across the bottom and knee high on the zippered side. This worked very well and I washed it weekly with my clothing.
I also carried this fleece sleeping bag for when it was too warm for the regular sleeping bag. Near the end of my stay in Arazona it was in the 90's during the day and 60's at night. For storage I just laid it undefvthecsleeping bag as it was the same size.
My mattress was a Therm-a-rest mattress that was self inflating as it has a foam core. It worked very well but it wasn't the same width of the sleeping bag so my body could end up off of it at night on either side. I would prefer a pad that was wider as I had the space for it under the sleeping bag.
I have to say that I can generally sleep on any surface but I also knew that my 106 days on the road would start to wear on make quickly if I didn't have a good night'so sleep. I did already have a mummy bag that was warm enough but I knew I would appreciate sleeping in more like a bed vs a bag.
I did design the rear of the Prius so you could fit two people in the back, but this would require a change in other aspects of living in and out of your Prius. Although I did not try two people the room is there. I would suggest two sleeping bags zippered together for the space. There would not be any place to sit in the back so once your in bed you are in either a semi reclined position old laying down.
Since I was by myself I could use the area behind the drivers seat as a seat for yet another position of comfort. When I would stealth I would open the rear door behind the drivers seat and get in angle sit down then sit on the edge of the bed platform and change to get ready for bed.
With two people stealthing would just mean getting into bed and changing clothes laying down. This may be doable but it would be interesting to see wirk for day after day.
It seems to me that two traveling in the Prius would use the back for sleeping thus eliminating the need to set up a tent. Stealthing could be possible but with a lot of work.
Since my fridge is located in the rear drivers side under the hatch, you can see in the picture that having this stay in the car with two trying to sleep would not work.
As I have stated in a previous blog if I was using the Prius for two people I would have a clamshell roof storage unit to store items as the space will be more than welcomed. You can rough anything for a weekend but living in and out of the Prius for months takes very deliberate planning and decision making on what you bring as every cubic inch counts.