How to get vacant home owners to sell?

[Peter Lee]

In my neighborhood, there are probably good handful of vacant houses that have been vacant for at least a couple years.   These people aren't even renting out their houses.  Any thoughts on good approaches?

And for those experts and this kind of stuff, what kind of success rate have you had?

I deal with commercial real estate primarily and usually you can strike up a conversation with a building owner but with single family owners I have heard it can be much more tricky.

I figure this is an ages old question so would be very appreciative to see tips of previous discussion or resources.

Thanks!