Yeah, second the taking weights out as needed tactic. You could also do bodyweight workouts in your living room - for inspiration, google things like 'convict conditioning', and crossfit, martial arts, or military workouts; also this
workout by Alwyn Cosgrove and this
one by Paul Plakas.
Personally, I couldn't work out in a hot, dusty garage. I guess you could make it amenable - don't know what yours is like, but maybe you could hose it down or use a leaf blower to get rid of the dust every now and then, and use a dehumidifier and fans, and drink tons of water while working out. (But personally, I'd avoid it.)