We're looking at getting a Solar Panel and Battery system installed possibly from Solar Zero in the near future and a couple of my co-workers at work (husband and wife who both work at our Auckland HQ/Showroom/Factory) had one installed by Solar Zero and when I asked them they said Solar Zero were fantastic.

 Anyway I looked them up and they say you need to invest $20,000-$30,000 if you buy outright and Westpac has a Greater Choices Home Loan at zero percent interest for five years up to $50,000 but Solar Zero also offers a subscription option.

So I would appreciate a rundown of both options pros and cons.