Hello how can I help you?
I'm interested in purchasing the sub box.  
Sure!
What's the best price you can give me for it?
I am taking it out for $50. I can give it to you for $45. This costed me more than what I expected to be made. They're custom molded around the latch and the inside of the tailgate. The box is going to fit in most vehicles universally. 
How about $20?
That's too low. The last I can do is $40 
$25?
I can do $40 last
$30?
$40 is last
I'll have to think about it some more then.
Tell you what, I can give it to you for $35 but then you will have to come pick it up! I wouldn't be able to deliver it ti you. 
Sure that's fine.