I have just bought a car with leather seats and I need to put a child seat in the back for a short time. Will it mark the seats or can I place something under the seat before I secure it in the car?
Will you be using the iso fix points or securing it by means of the seat belt alone? I would honestly go into the dealership and see what they recommend as appropriate ... as putting a barrier between the base of the chair and the leather may reduce the effectiveness of the restraint in the event of an accident.
I have leather seats and two child seats in for weeks and then change to another car, they look crumpled for ten minutes but soon go back to their original shape. I do use leather conditioner or leather wipes which makes it a bit more supple !!