Yeah, I always took that "under six" comment by Hesh to mean Tony's total worth - in cash and assets - was under $6 million. Earlier in the series, investigators estimated that Johnny Sac was worth about $5 million total. Believable figures, in my opinion.

In terms of assets, Tony had his house, the cars, his boat, and some real estate properties. His legitimate income was a large salary from Barone Sanitation. And, of course, all the tribute he received from the gambling, loansharking, extortion, scams, theft, construction kickbacks, etc.

Of course, as Hesh also said, Tony often spent it as fast as he made it. And anyone who has read about real mobsters knows they are as likely to bicker over nickles and dimes as they are big money.