It ain't easy running an Adventurer's Guild.
You have to deal with monster attacks, angry gods, and cowardly heroes. Money can solve a lot of problems (and motivate cowardly heroes), but a good strategy demands more than just bags of cash. You'll need to guide heroes as they grow from rookies into champions.
Let someone else do the dangerous work
There's riches to be found inside the dead city. Hire foolhardy and fearless adventurers to bring it back to you! Heroes will act on their own accord: slaying monsters, raiding lairs, and defending your guild outpost. Try to keep them out of trouble - their greed can lead them to bite off more than they can chew.
Find forbidden knowledge within ancient ruins
The old gods are jealous gods, and they will do all they can to keep their temples safe from intruders. Balance economic growth against steadily growing corruption. Defend your outpost from the encroaching monster lairs. Research ancient technologies and cast powerful spells. If you and your heroes can survive in the ruins, you'll be wealthy beyond your wildest dreams.