Need a little help

I'm looking for some things that maybe I should have figured out but for the life of me I can't [?]. One of them is how do you figure out the height (I understand by reading Y it will tell you your hieght)but what im wondering is there a certain way that you can get it exactly like you want (say 10 meters for example) w/o having to try to get the vertex on the exact spot, then its hard to tell if it is on the right spot b/c it uses the cursor for the height, which also gets me to is there a way to tell what height a vortex is besides passing the cursor over it. Next question is how exactly does the snap help out (understand it has to do w/ the grid and dragging) but is it better? Next what are some of the rules for banking the curves (woodies and steel), w/ woodies I know that you do not want to bank to hard b/c it will not be realistic? Well appreciate any help I can get. and know its makes me look like a dumb a$$ lol. Well I figured out how to tell the height of a vortex, just went into top few and clicked on the vortex and it was at the top. is that the main way to do it?