Yup. The MAJORITY of the replies you'll get from a post are SPAM.
One trick is to write in the post that you'll only respond if theres a phone number in the reply. And even then, there are still sp/cammers....

BE CAREFUL! Don't be naive and think every reply you get is an actual interested buyer.

A common scam is, when you reply to the "buyer", they tell you a story how they cannot actually pick it up but they'll pay extra for shipping, cause their in the army/africa/overseas etc etc etc........ DONT BUY THAT. BE SMART.