TomTop offers the Z02 GPS Car Charger Vehicle GPS Tracker in several colors (Grey pictured) for $12.29. Coupon code "DSZ02" cuts it to $8.29. With free shipping, that's the lowest price we could find by $3. It features two USB ports and GPS location via mobile app.
Note: This item ships from China and may take up to four weeks to arrive.
Use some marketing and merchandising tricks to make more money with less sweat.