I have done freelance work mostly related to graduation level problem solutions, but in one of my case I failed to provide the right solution, even after working quite good on it, so I refunded back the amount.
My question: what policy should one follow while doing some online work that, even though you work on that for at least some reasonable amount, should pay back to you for your efforts taken? Does anyone have the same situation where the final work goes wrong, even working hard on that?