Yugster offers the refurbished EcoXgear Rugged and Waterproof Bluetooth Speaker in Black, Orange, or Red, model no. GDIEGBT, for $29.97 plus $5 for shipping. That's the lowest total price we could find by $12. It features 3-watt stereo speakers, a 3.5mm jack, and fully waterproof design that floats.
Note: A 90-day Yugster warranty applies.