Pathetic Service on Parts replacement

Bought a brand new Mahindra Quanto, a gorgeous car but had an unfortunate incident one night when I hit 3 ***s on the way to Hogsback EC. Due to the fact that I was going so slowly, the damage was severe but was able to be repaired. The bonnet and a vender was replaced with parts from Mahindra. I took two kittens to be spayed and the vet was carrying the basket to the car and was admiring such a gorgeous car and he said look here there is some rust. When I hit home, my husband opened the bonnet and got the shock of his life, the whole front of the bonnet is rusted and rust on the vender. The rest of the car is on n absolute perfect condition. Phoned Mahindra with regards to this and they say there is no guarantee on parts. In May I was going to purchase the new Mahindra and have even been to choose the new colour etc., and have given this vehicle to our daughter as she has to travel far distances to where she teaches, but we have had a change of heart on the new purchase noe after this let down.