Tesla also purchased SolarCity for $2.6 billion in 2016, which gave the company access to the Solar Roof and Powerwall battery. These two products are currently sold together on Tesla's website and could still go mainstream despite Elon Musk's recent admission that the company bungled pricing badly enough for residential customers to file lawsuits related to unexpected price hikes that may be rolled up into a class-action lawsuit by a Californian court.