Seller stuck on Zestimate price

Hey BP,

Quick discussion and I hope to learn some bargaining techniques from this.

My last 2 off market leads were adamant that their property is worth "X" when clearly they got this number from a Zestimate (it was within a thousand or so both times). 

How do you all get past this? I understand saying that a zestimate is bogus and based off a fully renovated home ARV, but any quick tips anyone has used to get past this?

Thanks in advance,