It sounds like your new to growing....... Most new growers are all tripped out on "what will I yield" "how much per plant" "zomg wtf" and stuff. Dont be, just go with the flow. Pick quality strains and you'll be happy most of the time!
Yield is a factor that you cant really state even after your first crop of a plant. Your grow environment, feeding schedules, and everything, needs to be tip top before you can really crank each strain. Over time this will make more sense I can assure you......
To control height in a plant, you veg it less for shorter height, and more for taller heights. Plants tend to double or triple when they begin flowering before they are done. If some get too tall you can pinch and twist the branches that are too tall and that will help control things, and then next time chop a few days off your veg cycle.
Hope this helps!