Why do you even want a rear wiper? For me it's complitely useless...
Currenty my second car is Renault Megane Classic which doesn't have rear wiper, and I don't need it.
I think you only need a rear wiper if you have a hatchback car.Which has a lot of visibility and where you do need a rear wiper.
If you want better visibility on a Coop, get yourself a rearview camera mirror.
Can find them on ebay, about 100€ kit with camera and mirror.
And Coupe looks much nicer without the rear wiper