Thanks John for the suggestion of looking at the rebuffs. I have come across some misunderstandings mainly:
Firstly there was the typical misunderstanding. "Sorry, I thought you had come to read the meter". Funny thing here is that I did was not wearing my uniform, just chinos and army polo shirt. Perhaps she was waiting for the gas or electicity man.
Secondly there was the unusual misunderstanding. "No I won't contribute, I support a lot of charities. You can't join the lot can you?". I didn't ask him to join the band or sing of the songsters just some of his small change. The level of his committment is implicit in the question "Would you like to help the Salvation Army in their annual appeal". Perhaps I should need to make sure the question is more explicit. "Would you like to help the Salvation Army in their annual appeal by putting your lose change in this money box." Perhaps I could add "Although we do have an opening on B flat Bass if you fancy a blow."
Thirdly there was the lady who said "Oh! can I give it a miss today, thanks". It appears that she thinks the Salvation Army will be knocking at her door every day until she gives in and donates some money. Sadly I won't be able to do this as tomorrow I am out in another area - doing door to door collecting.