Walmart offers the Fujifilm Instax Mini Instant Film Twin Pack for $12.48. (Amazon has the same.) Opt for in-store pickup to dodge the $4.97 shipping fee. That's tied with our mention from a week ago and the lowest total price we could find by $2. It includes 20 credit card-size film sheets for Instax Mini cameras that develop similarly to a Polaroid.
Walmart offers the Insten Waterproof Camera Case with Rope in Blue for $1.89 plus $2.98 for shipping. (Rakuten charges about the same.) That's the lowest total price we could find by $2. It's made from soft TPU, which provides drop protection, will float, and is transparent.