Extra Buck is a Continuous Trap Card.
Trap Cards are normally Set first and can be activated on a later turn, often in response to an action.
On the current TCG and OCG Forbidden & Limited lists tracked here, Extra Buck is Unlimited.
YGOPRODeck lists Extra Buck for these formats: Duel Links, Common Charity, TCG, OCG, Master Duel.
A listed print of Extra Buck appears in 2016 Mega-Tin Mega Pack (MP16-EN095) at Rare rarity.
Among markets shown on this page, the lowest listed snapshot for Extra Buck is about $0.06 on Cardmarket (prices change frequently).
