For Prime members only, Amazon offers the Schwinn 20" Loop Folding Bike in Black, model no. S2280B, for $152.99 with free shipping. That's the lowest price we could find by $20. It features mechanical rim brakes, seven speeds, and an aluminum frame. When folded away it measures 30" X 32" X 11".

Note, it is currently backordered and will ship in 1 to 3 months.