Hi Buddy, just head down and see you at the end. Who cares what the results are? You will be closer to your goal of 150 than you are today. You seem to have exactly the right attitude, don't see what there is to lose. There is a member on here (Blue Frog) who put about 300 custies into his business within 6 months. He isn't a BS artist and he moved recently to a new area.
You need advice from people who have done something similar to what you are aiming at. The only thing between you and 150 custies is shoe leather.
I've always found that the best results are achieved between 1730 and 1900 in the week and anytime weekends. The trick is to knock when people are home. Sounds obvious, but knocking at 11 in the morning is rubbish. Try it and see how you get on.
Remember, the difference between the guys with a big custy base and the others is how often they canvass and/or leaflet. Like you said, it's a numbers game, that's how even the stupidest guys (Like me) can build a decent size business in this malarky. Some will, some wont, so what, next.