I've had some guidance from a client that they want me to hyphenate adjectival compounds (working-class residents) but not adverbial compounds (newly built housing).
But I keep coming up against things like goat-trading (a goat-trading business) and capacity-building that seem to me to need to be hyphenated.
Am I right (in the deeply ambiguous sense of 'right' that applies to grammar conundrums), and if so, why?