03'55AMG

My Buddy has a 1988 190E that hes looking to get rid of for another car (he has 9 already, mostly classic). But, recently he had me detail his 1986 Jaguar XJ6 (B E A UTIFUL CAR!!) and he was very happy with the job I did. so now he wants to know if id detail all his cars in exchange for his 190E. I don't know much, wait a minute, I don't think I know anything about these older Mercedes. he said the only thing it needs is a "cold start valve"? idk what this is.. but all i know is it is in beautiful shape for its age, interior is very nice. all opinions are much appreciated.