Frank's mother was out of her mind and way out of date when she claimed that old television with the fake wood paneling was worth a lot of money. She might have paid a lot of money for it in 1986 but that old tv isn't worth a nickel today.
I doubt she paid for it at all. I'm assuming that when VH1 moved the family into that rented house, it came furnished, or else a set decorator went right to work on it. I really can't imagine the Marescas going to the trouble moving all their own stuff from Rockland County down into the city and then moving it all back again after the show stopped taping.