I paid cash for mine, but have been absolutely delighted with the fact that I no longer pay any electricity bill,(was approx $400 a quarter), but have a credit during summer, because of the unused power I return to the grid.
I am in Brisbane, and went with RePlus Home Group, and I was pleased with their advice and guidance. They turned out to be honest.
I also have solar hot water. And because I am at home I can use power, especially hot water, mostly during the day, or early evening.
After install my bill was $20.60, the next bill was $90, because of changes the way AGL billed.
When I shifted to Alinta as a provider, my bill went to an $80 credit, then a $170 credit. They were better on all items on the bill, all the charges were lower, and the payment for what I returned to the grid was better.
So you will need to assess both electricity provider as well as installer.
Ask the installer to give you previous customers as a reference, who are a similar family and situation to yourselves. And talk to them.
There seem to be so many crooks in the solar marketplace, its like dealing with second hand car salesmen. But there are some really good ones too.
I was ready to sign and then all these small things in the contract came up... I asked again and again there is no out of pocket costs...
then the contract said 360 to change the box....
There was another sneaky charge I forget and they slagged off the previous one saying they didn't know what they were talking about (the offered a battery box because of my usage is unique and I use a lot of power at night)
I'll look at replies thanks