Lets go over your options, shall we
If you did bargain and sacrifice an artifact, enchantment or token of some sort you'll cast it for free if its mana value was four or less
Is an Enchantment a Permanent
Lets apply this concept to a specific example, the Stone Tongue Basilisk deck: 1-cost cards: Llanowar Elves, Fog, Rangers Guile, Giant Growth 2-cost cards: Rampant Growth, Mulch, Grisly Salvage 5+ cost cards: Natures Revolt (costs 5), Stone-Tongue Basilisk (costs 7) In this example, the distribution would be 16 cards with a mana value of 1, 12 cards with a mana value of 2, and 8 cards with a mana value of 5 or higher
On average, dropping her on turn three nets you a good five to seven cards when you finally bring her back, and in a Temur or Simic Lands build