DazzleGames via eBay offers this TPU Rubber Ultra-Thin Bumper Case for iPhone 6 in eight colors (Clear pictured) or iPhone 6 Plus in five colors for $1.99 with free shipping. That's tied with last week's mention as the lowest total price we could find for such a case by $3, outside of other eBay sellers. It features TPU rubber construction.
UltraProof via Amazon offers Prime members the Tethys Movee Waterproof iPhone 6 Case for $12.99 with free shipping. (Non-members can spend over $35 for free shipping; otherwise, shipping adds $6.07.) That's the lowest total price we could find by $6. Note that this protective case does not feature access ports to the headphone and charging ports; it's also not compatible with the TouchID sensor.