Walmart offers The First Years On-The-Go Booster Seat for $13.97. Opt for in-store pickup to avoid the $5.99 shipping charge and drop the price to $10.38 $9.97. (Amazon has it for pennies more.) That's $3 under our March mention and at least $3 less than you'd spend at another local retail store. Designed to support up to 50 lbs., this self-inflating booster seat features a T-restraint and carrying handle.