The great debate in SaaS seems to be: touchless? or sales reps? And the answer always seems to be some combination of both. One of the biggest success stories today is InVision -- they started with a freemium model and over the last few years have layered on an enterprise sales funnel that new accounts for 50% of their revenue. Here's the story behind how they did it -- and 4 lessons from InVision's SVP of Sales.