Has he came to look at the bike? I would say if he has not expressed an interest in looking at the bike or test riding it then it is probably a scam. Since most craislist buyers are local to the area you post they want to see before they agree to buy. We just had DH's old mountatin bike posted on Craigslist in Seattle and this is the first reply I got:
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Hi,
I've just gone through your ad and I'm interested in buying. I'm presently in NY on an assignment but I can arrange your payment from here and It will only take 3 business days before the payment will get to you. I will be adding $20 extra for you to keep in my favour. Money Order is the only means I can pay you with at the moment. If this is acceptable by you, Please send me your full name and address where the payment will be sent to, so I can send your payment. I will make arrangement for the pick-up once you receive payment
Thanks
Tara
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I knew this was not legit so I never even responded. The second response was a legit buyer who wanted to come look at and test ride the bike.