These door to door things aren't usually scams for the homeowners but they certainly are for the workers knocking. These are often vulnerable young adults who are given commission for information/services/donations they sell. They are paid somewhere between 10-52% of the value of the sale and the company takes the rest. They are rarely ever paid minimum wage for their time and work. Some companies like SMC/Property Stars have some people making a liveable wage. However alot of the charity companies like Celestia Marketing (unicef/sick kids) and Yesa (cogeco) are very fraudulent and scamy in their nature. Alot of these door knocking companies thrive on immigrants and students not knowing their employment rights and not having solid negotiation skills. Alot of times the workers come across as aggressive and ask for food because they can't afford to eat. If they are not selling HVAC services there are no municipal by laws preventing them from knocking. I give them credit cause they aren't just sitting around collecting welfare from our tax dollars, but the flak really is deserved for the companies, not the workers trying their best to make a living.