tell her to show you a receipt or some sort of proof she purchased it for that much. i'm sure she didn't pay $2,500 in cash so receipts or credit card statement.
i honestly would not buy it. good price but a NIB treadmill being discounted over 80% of what she paid is very suspicious. not to mention, you can't test it out?
if not, tell her to bring it to your house and you'll set it up there. if everything works as it should then you'll pay for it. if she's an honest seller and knows it's new then she has nothing to worry about.
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