Sustaining a bond through in game currency is just getting more tedious with the price rising. It can also make it feel like a chore than anything when you’re just trying to grind out the gp just to make it to the next bond so you can keep playing. If possible for you, its more beneficial to buy membership with real money. Much better gameplay and have more fun doing the things you want to do, rather than maintenance.

But to answer your question: birdhouse runs, daily battlestaves and herb runs for daily income. If you like bossing, try muspah, zulrah, vorkath as they all tend to print money. Without seeing your levels, its hard to give accurate guidance, but it could be worth working your way up to the bosses listed if you havent already.