170,000 = $850 off your grocery shopping.
Remember, nothing is for free so ensure you get other quotes from independent suppliers to see if the $850 has just been built into the solar quote from Origin. Might be nice to have if you are already planning on going with Origin.
e.g. ACT has a deal where if you go from gas to RC air con, you get $1500 off when you go with "approved installers". Both of these installers are owned by the same mob that essentially run the energy game in ACT. When I called up an independent guy and asked about the rebate, he laughed and said, he'd quote me and if the price was above the approved installer quote, he would take off $1500 his quote. Sure enough, his quote was $1500 under the approved installer quote before the rebate, ie the same price in the end as the approved installers just add on $1500 only to take it off again via the rebate.
I wonder if it's allowed to install on the roof of a unit or an apartment?