I don't buy it

[keannu]

1.When you say "I don't(can't) buy it", sometimes it means "I don't agree with your opinion" for another's opinion in meetings, but in this case, does it mean "I won't buy such a cell phone" or "I can't accept your action"?

2.Also, when you say "You(I) got this new phone", does it always mean "obtain" or sometimes "purchase something"? Does "get" have the meaning of "buy"?

ex) Woman : Hey, look at my new mobile phone. Isn't it cool?
Man: Yeah, It looks like the latest model.
W: Sure it is.
M : Hmm...Didn't you change your phone only two months ago? What's the reason you've got this new phone?
W:Do you know why? It was free. The company held a special event for customers.
M: I don't buy it. There must be a trap. What are the conditions?
W: There are a few, but I can't remember them exactly. Who cares about the conditions?

[5jj]

M : Hmm...Didn't you change your phone only two months ago? What's the reason you've got this new phone?
Could be "you have [=possess"] or "you have obtained/bought/received". If the latter were intended, it would be more likely as "you got".

W:Do you know why? It was free. The company held a special event for customers.
M: I don't buy it. I cannot accept/understand that explanation.

[SoothingDave]

He doesn't believe the company really gave the phone away for free -- which is why he asks what the conditions are.

There is no such thing as a free lunch.