Ahhhh. Golems.
In this case, I will agree with the earlier posts and say, attack them one by one, while they're still neutral.

Cheap, but legal.
Stone and Clay are covered. For the Iron Golem though, you can also try this. Use a thief, and lay traps around it. About a dozen and a half.
Rest to restore traps as necessary.
The traps will remain even after days of resting.
Get someone from the safety of the door, to shoot the Iron Golem.
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The Iron Golem roars!
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The Iron Golem gets impaled over and over again and falls. Defeated. If still not dead, O_O?! summon a few tough creatures to tank for you while you scratch it to death.
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If not a Sorcerer, than a Paladin.