The ƒ-1.7 lens on that camera is worth $50 to $100 or more, depending on its condition. The camera, in good condition, is worth $50 or more by itself.
If you are a good garage sale hunter you might find one for cheap. I got mine at a rummage sale for $20. You got yours for zero dollars. Right?
So, ask yourself... Is $70 a good price to pay to repair a camera that could have cost you $100 or more?