Market Trading Can You Earn Money ?

I think this is a difficult one,I worked on markets for a good number of years,getting up at 4am and arriving home at 7pm and quite often not even taking my rent and fuel costs.In fact at the end of my last year i worked out that i infact made less than two pounds an hour,and yet it seemed that i was always desperate for stock even though people constantly told me that i had a fantastic range for a market stall selling fishing tackle.
I used to think its my product there is so much competition out there,but to tell the truth the only person i knew that was making money was a guy doing key cutting,watch batteries and jewelery repairs,but even he was putting in 80 hours a week.Then i found out that Car boots on a Sunday were the best bet and i was home for 3pm,another lesson that i learned was dont buy anything unless i can at least treble my money,ie sell for at least three times cost.the shops do when they sell during a sale they still sell for double cost and plus some.
Ray