A friend of mine had his car repaired by a local Mercedes indie shop recently, and when he picked it up he noticed a small scrape that wasn't there before he took it in. Are repair shops liable for any damage they do to a car's body?

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1978 450SEL (Pearl white, bamboo interior, 97k)
1959 Impala (2 dr. Hardtop, red, white int., 283 V8, 45k)
2003 Tiburon GT V6 (Ultra Sports Pkg. 3, red, blk int., 13k)