Wealthy Market

Wealthy Tradepost enters the battlefield tapped.
{t}: add {c} or {u} to your mana pool.
{t}, target opponent creates X colorless artifact tokens named Gold with "Sacrifice this artifact: Add one mana of any color to your mana pool" : gain control of target artifact with converted mana cost X or less. (The opponent creates the Gold tokens as part of the cost to activate this ability.)
Everything has its price.