Did they live like the nobility (i.e. lavish homes, servants, the like) or did they have more modest lifestyles? How did they dress? What sort of professions did they have?
Many lived in different ways. The third estate was very large. Wealthy is a difficult term. As their was such income disparity during this time, the middle class were 'rich'. So for instance lawyers and merchants could dress reasonably well and might be able to afford a servant and have a decent multi-room apartment. Robespierre was noted for dressing very well yet he did not really live in much luxury. Their were few during this time that had lavish homes. Danton on the other hand lived in an upscale home for a time. Wealthy members of the third estate could lead lavish lives quietly if they vocally supported the revolution after the King was imprisoned. There were not a terribly large number of wealthy people in the 3 estate. The mass majority were laborers, farmers, servants etc.