The challenge for Tesla in folding SolarCity into its business is to generate enough money to justify the acquisition and associated debt. In the third quarter of 2016, the final quarter SolarCity operated as an independent company, SolarCity had $257.7 million in operating costs, including $204.2 million of SG&A and R&D expenses. Extrapolated over an entire year, Tesla took on $800 million in annual operating costs that would need to be paid for somehow.