Getting the seller to say yes!

[Philip Bashaw]

Does anyone have a good strategy or recommendations to get the seller to say yes to your price? I'm interesting in acquiring properties to wholesale and possibly fix and flip. I have 2 semi-motivated sellers sitting on vacant properties and 2 properties that are in a high end flip area (buildable lots go for $350K) that have been vacant for years, but the owners refuse to sell and keep up the maintenance (at bare minimums) to not alert code enforcement or piss off the neighbors. However, they remain vacant and slowly deteriorating. 

Has anyone ever broken through on stubborn sellers? 

Also, what are some motivating questions to ask the semi-motivated sellers? or any seller?