I used to buy green d'hides, tan them and re-sell them to make profit. Can this still be done?

Yes, there's also lending of certain items...such as godswords, sara swords, certain armor, rune, and so on......

 

But its harder to get green D'hides nowadays because of crashing revenants :roll:

There were Revenants when i was training range on green dragons, so I don't think that the green d'hide market would have went down too much. Can't wait to get back on runescape. (made a promise to myself to stay off until september)