I would have to agree with Sunsanvil, while I paint mostly with acrylics, and vent everything outside, you really don't need to if you are using a NON solvent based paint, something like Vallejo.

That being said...you can always attach your vent from your airbooth to a piece of board that is the width of your window, and only put it in when you are using your airbooth. Take it out and close the window when not in use.