I say, and with God's success: It is better to start at the mosque before unloading one's burdens if that is feasible for him. If they are a group, some of them can engage in unloading the burdens while others perform the actions, and he should not delay it for changing clothes, renting a house, eating, drinking, or similar matters except for a valid excuse. If that is not feasible for him, he should unload his burdens first so that his heart is empty. And God knows best.