I only spot spray with Gly at my parking lots. I go through the lots every 4-6 weeks. Retail accounts, that is why I just spot spray. I also use a back pack sprayer doing the same thing. I know there are guys that use the booms but to me there is way too many things that could go wrong. I prefer staying small and stealthy. Also I am not spraying where there are no weeds. With a boom and gly, I am afraid of drift. In and out. I use1 qt per 10 gals. water. As long as it the leaf gets wet it will kill it. I also do the outer edges of the lots / side walks and often there are larger weeds and grasses. I called the folks at Round up and that is what they suggested for my needs. It works well for all of my applications.
I too just got my licensed recently. I went and bought a used Permagreen and have just used around our home and family. I have much to learn with it. I have it calibrated and have only ran 12 gals of fluid through it. Before I go out and apply, I want to make certain that I am correct. So far around the house with just a little 2-4-d the broad leaf is fading fast and the grass is still growing. Nothing killed but what my goal was. I have also spread some weed and feed in a few spots. I am in no hurry to get out there. I like you am going to continue my education process before I get out on some one else's turf.