Walmart offers the Storkcraft Long Horn Bunk Bed in Espresso, White, or Pink for $179 with free shipping. (Amazon charges the same price in Pink and White.) That's the lowest total price we could find by $91. It converts into two separate twin beds and includes a full-sized slat roll mattress support.
Walmart offers the Storkcraft Savona 2-in-1 Convertible Crib in Espresso, model no. 04550-419, for $99.99 with free shipping. That's the lowest total price we could find by $25. It can be configured as a fixed-side crib or full-size bed.