These in-person sales were sometimes effective, but it's not hard to see why Tesla would shake up its strategy. It's indicative of a maturing home solar energy market, particularly in Tesla's home turf of California. Why chase after fewer and fewer customers through sales reps, especially when you're effectively asking homeowners for an on-the-spot commitment to a solar panel installation? Tesla has already said it would focus more on saving money with its solar business than boosting its sales, and there's no question that face-to-face sales are expensive when success is far from guaranteed.

As it is, SolarCity's methods aren't exactly in sync with Tesla's upscale, relatively low-pressure sales approach. While the electric car and solar panel groups sometimes aim at very different audiences (one is eager to splurge, the other is trying to scrimp and save), the end to door-to-door sales should create more of a united front when Tesla pitches its eco-friendly vision of the future.