My Ford Kuga has a leak - what are my rights?

I bought a Ford Kuga from a local garage in November. The car has a leak and, on further inspection, the leak is coming from the window seal and from the engine bay where the metal seams meet. Is this...

After carrying out an oil change, the sump plug is leaking - could it be because I used a metal washer?

After carrying out an oil change, I have a leak from the sump plug. I used a metal washer from the filter pack, not a copper one, as I would have expected to seal the sump plug. Could this be the cause?

Why does the temperature gauge go into the red when going uphill and return back to normal on flat ground?

I just had the timing belt, water pump and exhaust sensor changed after finding a leak. Now, when the car is going uphill the temperature gauge is going into the red, then dropping quickly when on the...