1. Bust: The arrow dives and so too do the moneychanger's fortunes. Not only does his spell only work at 1/2 strength, but any Golden Promises he has to his name are halved in value as well.
2. Stand Atop the (Corpse of the) Little Guy: The spell will work, though a victim must lose some treasure or at least have their work lambasted first. However the moneychanger does so is fine with Geedeepee, just as long as its paid.
3. Reap & Reap Some More: What better way to get slightly ahead than to rape the earth? As the spell occurs, the nearest 1d6 x 10' diameter natural area in a random direction suffers some deprivation, whether it be (roll 1d4)  spoiling of the plants and soil,  collection of noxious refuse,  insidious harming of the health of any beasts or folk there, or  all three. Druids and other Nature-lovers will take a very dim view of this effect.
4. Oh, Geedeepee: The Arch-Devil's 'prosperity' abounds, with all within 1d6 x 10' of the spell's casting experiencing one of the following effects (roll 1d3):  have their wealth adjusted by +50 to -60% (1d12-7 x 10),  become physically ill, suffering -1 to Strength, Dexterity, or Constitution, or  become mentally ill, suffering -1 to Intelligence, Wisdom, or Charisma. The latter two effects last for the next 1d12 days unless cured beforehand.
5-8. Standard Casting: Apart from the mysterious signs of money, whispering of arrows, and/or moaning of lives and lands ruined, the spell occurs normally,
9. The Path to Success: If the moneychanger is willing to spend at least 1d10 x 10 gold pieces at the next buying opportunity he has (preferably on frivolous things), then he can increase the spell's range, effect, or duration by 50%.
10. It's in the Numbers: Luckily for the moneychanger, the magic's range, effect, or duration is automatically boosted by 50% with Geedeepee's devilry, though he may still wish to consume wantonly anyway.
11. A Capital Notion! All it takes is a can-do attitude to get ahead, for those who can't enjoy rapid growth are just too lazy to appreciate it! If the moneychanger takes some initiative and decapitates or inflates to death a victim by the next dawn, then his spell's effects, range, or duration can be doubled.
12. Boom: The arrow soars and so too does the moneychanger's magic, enabling him to double its duration, range. or effect, not to mention the value of any Golden Promises he has.
Next week: Moneychangers of Geedeepee, Part III!