Celebrim
Legend
As seldom as possible. I try to nudge my players away from recruiting NPCs into the party. I hate running party-NPCs.
In point of fact, I do as well for a lot of reason - not the least of which is the players risk deprotagonizing their own characters. I admit I'm looking forward to the game situation changing such that recruiting NPCs isn't quite as viable of a strategy. But in urban adventures, recruiting NPCs is often a rational approach if you have the resources to do so. The more removed from 'civilization' and the higher level the PC's become, the less effective recruiting NPC's is likely to be. At some point, they are going to realize that low-ish level minions are often a liability rather than an asset. I suspect they'll take some meat shields into the next stage of the adventure. I don't expect any of them to come back alive.