Need to earn a bit more cash.!! does mystery shopping provide a small but reliable income in anyones experience? Also - how to you declare the earnings?.The website i looked on said you need to declare earings but can off set some things such as petrol- web site says refer to your accountant - i dont have and could not afford one ! any advice?- never been self employed before and simply dont have a clue how to to tax stuff.!!! thanks !!