Google's entry-level Nest Doorbell, one of the best models available, is on sale for $139.99 ($40 off) at Amazon, Best Buy, and Target ahead of Amazon's Big Spring Sale. Unlike Ring's $100 battery-powered Video Doorbell and other companies, the Nest Doorlocks don't require a paid subscription for smart alerts. They can be notified for free via the Google Home app if the doorbell detects a person, package, or animal, and offer up to three hours of event-based recording. The camera records video at 960 x 1280 resolution and offers up to 6x digital zoom, making it easy to identify visitors and packages. The doorbell also supports night vision and two-way audio.