Carbon filters are the tried and tested odour control solution, you can have the exhaust fan pulling air through it or just a small fan moving air through it inside the room.
Diy filters aren't difficult to make if cash is tight, look in the diy section of the general marijuana growing forum for instructions.

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Originally Posted by ceestyle
Don't be a martyr wasting $100 or more on CFLs to prove they're inferior for flowering pot.