I thought of charcoal filters but even though I used overspray filters, I think they'll load up with paint spray to be effective for any length of time. Yes, its the neighbors I'm concerned about. I've sprayed 25+ days, but the neighbors complained once and the police came a knockin, so I want to minimize the chance of that happening again. I'm allowed to spray 2 cars/year. Never thought of the low VOC stuff. I'll have to call Barry to inquire about the drawbacks of it compared to Universal clear.
Spraying primer is low risk, not much overspray being ventilated. Base is OK too. Its the clear that creates the cloud. I though some type of wet mist in the exhaust duct may help as well or a swamp filter others have spoke about.