It's trivial getting gold down to zero, your stash showing character can keep wisdoms and transmute shards/skill gems. Wisdoms sell for 2g, shards for 1g. Since there's no migration, if you don't show your stash, you could have anything in there, it's the only way to ensure fairness currently, if you want an official run.
Gem skills also sell for 1 gold, at low enough levels at least. I've just got a character that sits in act 1 town with extra skills/wisdoms to vendor and to prepare for the rule about showing tabs prior to starting.
Since gold persists for the whole league, I've been clearing my gold down to 0 by buying and selling until I get a multiple of 25 in my gold. Then just buying wisdom scrolls at 25 a piece since the migration feature isn't available. It does basically lock out a whole league for practice though in the current state.
