Exact Measurements - or resize to specific dimension I’m pretty new to blender and started with sketchup. I find overall that it is much more powerful software that is generally not as buggy - and can be used for many more things. 

Still, I struggle with one tool in particular, the measure tool. When I want to measure from a vertex to vertex, I turn on snapping and can use the ctrl key to snap to the second vertex but for some reason I can’t do that with the first one. And so I zoom in very far to click on the first point then go all the way across the the other point. It is always wrong - really. So I zoom in even further to the first point and I see that it didn’t snap to this point. I mean, with ALL of the amazing capacities of blender this definitely surprises me.

I’m not expecting the great features of the measure from sketchup like resize the model by measuring a distance and rescaling it to that size - such as for a doorway or table height or other known quality, nor for the easy snap to x y or z direction. But am I missing something - is there a good snappable add-on I don’t know about?

I realize that blender is not a cad software, but I hope you understand that the measure tool seems super underdeveloped given the other aspects of blender that are now so sophisticated.
Thanks for any clarity!
First point can't currently be snapped from the start.
It is a known limitation that is currently being looked at, it is part of a broader limitation that includes among other things not being able to set a base point for moving before transforming
Current recommended workaround is to eyeball the first point, precisely snap the second one, then return to the first one and move it while using snapping.

Edit
As of commit Gizmo Library: New Snap Gizmo from 27 May 2020, there is now a new generic special type of gizmo whose purpose among other things is providing snapping before use for various tools and operators in Blender, like base point snapping for transforms such as move or rotate, or snapping the first measure point of a ruler without having to backtrack