Here's how to save $500. A lot of times sellers will say as part of their pitch for a vintage bag: "it comes with a box." This is often said within the context of a bag coming with its box being of better value.
What you need to know is that only original boxes are of value.
Let me show you. On most vintage Chanel boxes back in the day, they would have this product sticker. As you can see here, there is a sticker here with a serial number.
If this serial sticker actually matches your bag, then yes, this is a very valuable box. If this is just a random serial sticker, then this is just a random box.
So next time, save yourself $500 and ask: is it an original box? Because if it's not, it's just another paper box.