Walmart offers the Funko Pop! Batman v Superman: Dawn of Justice Batman Figure, model no. 6025, for $8.95. (Galactictoysllc via eBay has it for the same price with free shipping.) Opt for in-store pickup to dodge the $4.97 shipping fee. That's the lowest price we could find by $4, excluding the below mention. The figure stands 3-3/4" tall.

A close price: Your Favorite T-Shirts via Amazon has it for $9.30 with free shipping.