Car won't be fixed

I bought a Code 2 vehicle in April Barlowworld Bruma T/A Ford Bruma so now is not even 6 months driving the vehicle is making some funny noise when I drive, I called them to ask can they check it what's wrong I'm told I must pay R800 for the vehicle to be checked so I enquire from the people I dealt with when I bought the car I get a reply " Yes, You're responsible for service maintenance of the car" and when I asked why doesn't it come with any warranties and I was told it comes with extender there's now no reply.... I have no one to contact except them all I get when I call is that I must book the car in and pay R800 how fair is this though?