think there a completley seperate rearward facing seat it the boot loose your boot space when your using them (there like the ones in a volvo )the ones ive seen on ebey they look huge so think you wont be able to fold them away .
It's the size/age of the person that determines whether a booster seat is needed or not.
The seat is probably too small for a booster seat to sit properly on the seat anyway.
I personally do not like the seats in the back of these cars.
The "boot" is part of the crumple zone - I wouldn't put my kids in there.
I know these cars were around before manufacturers started taking car safety seriously, but they are getting old now.