Nasty car crash :-(

Recently, a black BMW stopped suddenly without cause in front of me resulting in a rear end collision. He then sped off. As you can see my car's a write off. I'm hiring a car for 3 weeks (£651) in the wait for a mobility car. Please, any help would benefit me. PayPal, buying clips, joining my site, booking me, posting me a penny haha! I can't believe the cheek on people!