I had a long term illness which forced me to be housebound and I got so sick of the people knocking on the door. After one week where there was over 10 people coming to the door I made up my own sign. Hope it is ehell approved.
To Visitors To Our Property
We don't want to change our phone supplier
We don't wish to change our power supplier
We are happy with our gas supplier
We don't want to change our internet supplier
We are happy with our mobile phone supplier
We don't wish to change our garden man
We don't need cleaning supplies or household goods
If we want something, we will research it ourselves
If you ignore this sign, don't be offended when we shut the door before you finish your spiel.
Three hours after I put the sign up at eye level in the window next to the front door, I saw someone with a clipboard walk up the driveway, stop to read the sign, then walk back down the driveway. Success. A couple of days later I had a couple of guys walk up the driveway, read the sign, then knock anyway. They asked if we didn't want to donate to charity as it wasn't on the list, and I said I was happy to talk to charity workers as long as they understood I would only donate if I wanted to, not because they guilted me into it. They were happy with that and despite me not donating we did have a nice chat.
Since the sign has gone up over 3 years ago, I have had only one person ring the bell that wanted me to swap my phone company. As soon as he started his spiel I pointed to the sign and shut the door. I have occasionally had some religious people ring the bell, but since my neighbour has scared most of them off, we don't get many of them here. And other than my Avon lady that I told to personally ignore the sign, we have been left alone.