I bought a killer mandolin on Reverb, made two mistakes. Told the buyer I was excited and couldn't wait and I would give it a great home, along with packing instructions.
Mistake # 2, posting about it here.
Somehow the seller suddenly had a change of heart, "Mom wanted to keep it in the family" after it had been listed for 6 months and he'd lowered the price.
Don't tell buyer's you're excited, it makes them suspicious.
Don't post about anything you don't have in your hand, but I usually break this rule without issue. Worst case scenario - it would never happen here of course - is that you're posting about a great deal, too good, and anyone can contact the seller and entice him to get cold feet for more money, would be pretty low, but I've seen it happen in real life time and time over... iYou're buying something at a price that suddenly turns into an auction, I don't play that game at all, either way, it's nutty unethical but it's the norm nowadays, people think effin Craigslist is an auction site.
Me, calling about a guitar on Craigs for $375, "Do you still have it?"
Seller: Yes, I'm taking offers.
I'm thinking to myself, if you still have it it can't be that great, maybe you should be taking a lower priced offer to move it, that's what usually happens when seller still has his item after it's been listed for a while.
Me, "I'll take it for $375."
Seller "I've already got an "offer" of that much", meaning I need to beat this imaginary offer to swing a deal.
Me "Goodbye." It's much better to get off the phone before telling someone what you think about them.