Hey! I also have several workout DVDs, with some ranging from a progressive 12-week plan to others just being a simple 15-minute ab workout. I find it easier to fit in exercise and be consistent when I switch things up (maybe one day I take out a DVD that focuses on abs, while another one is a dance workout). Especially if you do some sort of alternative workouts (dance, Zumba, etc.) it may not feel like such a chore to workout, and before you know it, you'll have been moving for 30-45 minutes.
Since you're in the field a lot for sales, do you ever have time to squeeze in a quick workout during the day? Even a walk, if you don't have time to shower/get cleaned up between the workout and another sale? If you travel a lot and stay overnight, look at going for a run or walk a chance to explore whatever area you're in for that day/part of the week. (Again, something to visualize so it distracts you from the fact that you're working out.) Hope this helps!