I don't think that they can touch your physical assets. Credit card debt is generally unsecured. And if they have already sold it off to collections, your credit record is already impaired-which is usually the biggest threat they have over people. Once they've done that you really don't have as much to lose any longer.
They could theoretically take you to court and attempt to get some sort of wage garnishment but again chances are that they would rather come to some sort of reasonable settlement.
But no they can't just dip into your account on their own. There's even rules over how they are to interact with people. An attorney or legal aid in your area could point you in the right direction. Collections agencies run on intimidation and ignorance of their limitations.
"When the snows fall and the white winds blow, the lone wolf dies but the pack survives."
Winter is Coming
Now this is the Law of the Jungle—as old and as true as the sky; And the wolf that shall keep it may prosper, but the wolf that shall break it must die.
As the creeper that girdles the tree-trunk, the Law runneth forward and back; For the strength of the Pack is the Wolf, and the strength of the Wolf is the Pack.
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