i think it is not such a difficult job you can do it very simply, you can exchange bitcoin into your local currency in exchange and then can also buy bitcoin if you feel that it is the good time to do so.
Yes , but it has a risk behind them . Especially you sell it in online sites , who knows you would be get scammed or it's just fake sites to stealing your money . But , as long as you sell it in the right place and has a good reputation you should be fine .
In online ever where you can find scammers so when you want to buy or sell something always should go with reputed sites even though they may charge a slightly higher fee for the transaction. You can find trusted sites list on this forum to trade. Don't ever trade on any new sites just to avoid transaction fees.