This TP-Link HS210 Smart WiFi 3-Way Light Switches drops to $16.61 Amazon. Shipping is free for Prime members, with a free Prime trial, or on orders over $25. Otherwise, it starts at $5.99. This was the best price we found by $8. This light switch has built-in WiFi, so you can control and program it with a smartphone, tablet, or voice-controlled device like Alexa or Google Assistant. This version works with three-way light set ups. Sales tax is charged in most states.