Faulty car

The starter packs up on a new Renault Sandero 2018 model barely 4 months old. Get told it takes 48 hours for a courtesy car ?48 hours what exactly am I supposed to do without a car for lord knows how many days.the manager at Renault Northcliff shrugs and says they only have 8 courtesy cars as a custom how is this my problem. Renault was the worst car purchase I ever made. Quiet frankly I don't even think I want it anymore and looking at the consumer protection act I am well within my right to return the car.