Tesla has started selling its Cybercab for personal use, and this is a bullish signal for the stock because it opens a new, high-margin recurring revenue stream.

• The Cybercab costs under $30,000, but using its self-driving feature costs $299 a month, way more than the $99 a month Tesla charges for self-driving on regular cars.
• Right now it's invite-only and limited to Austin, with deliveries possible as soon as December; owners can only use it for personal trips in a limited area, not as a taxi.
• Owners still have to pay for insurance, registration, charging, and cleaning, and Tesla can shut the car down remotely if rules are broken or payments stop.
• This is a shift from Tesla's earlier plan to keep all these cars for its own taxi fleet, suggesting Tesla would rather sell cars and collect subscription fees than run a taxi business itself.
• Most of that $299 monthly fee is expected to be high-profit for Tesla, since basic maintenance costs are small; at scale, millions of these cars could meaningually add to Tesla's profits every year.

Outlook: Expansion beyond Austin depends on regulators and how fast Tesla can get self-driving approved in new cities, but if it scales, this subscription business could become a major, recurring profit driver for Tesla.