Toyota Repair: brake lines, generic answer, would make sense

Question
my mec says all my lines are boxed togeather and because i have a leak in my brake line i should change them all so it will cost 500 dollars is this accurate   thanking you in advance randy 1998 corolla  

Answer
You did not tell me what kind of car this is so I will give you a generic answer, I have no idea what your mechanic is talking about, it would make sense to me to only replace the brake line that is leaking, maybe more clarification is needed because I'm not sure what the question is.