Sold as seen what does this count for?

Long story I sent a close friend of mine to go and look at a car that was being sold by a private seller that I had seen online I couldn't go myself as I was working! Anyway I was told the car was clean and tidy so a deposit had been left then came the bit where the guy selling it had told my friend he thinks the tracking may need doing sometime soon as it had a slight pull occasionally I looked it up online and seen it was only cheap so wasn't too mad, Next day I went with my friend to collect the car and paid the rest of the cash he filled in the log book with my details and I signed it he gave me a receipt for the sale stating 'sold as seen' On the way home i notice it wasn't a litle pull but quite a strong one! After getting home i removed a thin black tape from the bonnet (go faster stripe) to notice the bumper was 2 totally different colours and after a closer inspection (which i thought my friend had done) I noticed a lot of bodged up areas which got me worried so I took the car to the garage where I was told this car had a completely new wing most likely due to a smash so now I have to wait until friday to get it on the ramps and a good look over as it's probably due to the smash why it pulls needless to say I am not happy as I wasn't told it had been in a smash I wouldn't of touched it as I have 3 young children, I have tried calling the seller and it just goes straight to answer phone what can i do ?