Stretchy makes some good points there ^^^^ . I will add to that excellent advice by being a little bit more detailed.
At some point or other there must have been one or two leaflets that paused with you for a while . . . . . before you put them in the bin LOL What was it that got YOUR critical attention? And that the the essence of an effective brochure.
I see any marketing/sales literature as being your "portable showroom" so always treat it as such. It is a VERY effective tool if you take it with you out door knocking. You cannot lug around a set of stairs with you (obviously) to show the quality, but some excellent photos of your best work will speak far better than any words, plus it is an excellent sales prop to support your pitch.
Finally, using your product knowledge, experience and most importantly, your enthusiasm, door knocking is not as frightful as some people imagine it is. Relax, go with the flow and speak slowly and clearly with a big smile on your face. The biggest benefit to you for door knocking is that you can see at first hand the sort of properties that are most likely to be in the market for your product, instead of carpet bombing every single house in the area. Get chatting to people and you may find they were contemplating having other other products like a balcony they want building by a craftsman, or they may refer you to other people.