Amazon offers the Lil' Rider FX 3-Wheel Battery-Powered Bike in Yellow, model no. 80-KB901, for $52.99 with free shipping. That's the lowest total price we could find by $27, although we saw it a month ago for $3 less. It features a top speed of 1.75 mph, sound effects, headlight, forward and backward motion, and 66-lb. weight capacity.
Of note, it's also available in Black for $55.99 (a low by $24).