Ryobi 18V ONE+ 150mm Circular Saw Tool Only $79 (Was $99) + Delivery ($0 C&C/ in-Store/ OnePass/ $99 Tools) @ Bunnings Warehouse
O O 
Just spotted this price drop. Annoying, as I paid $99 about 2 months ago.
Plenty of stock around with not too many stores nil stock. https://nrby.in/bunnings/0488986
My reason for buying it over a larger saw is because I just don’t need the extra cut capacity, but your needs will probably differ.
The blade choices for this size saw blade are more limited than a 165mm saw, but there are options.
This saw has a 10mm arbor, however, if you grab one of these $3 reduction rings you, can use any 150mm x 20mm arbor x 1mm or thicker blade. Can verify the rings are 1mm thick. https://www.ebay.com.au/itm/395405241703?var=664072009620
Bosch have a few inexpensive ($20-$25) 150mm x 20mm arbor x 1,2mm thickness blades available. https://www.amazon.com.au/s?k=bosch+circular+saw+blade+150mm…
Also there are also quite a few 136mm blades with 10mm and 20mm arbor size available, just bear in mind you will lose 7mm cut capacity so may not be the best choice. Plus the tend to be a bit more pricey.
There is also this 140mm blade for $23. https://www.amazon.com.au/dp/B00I527PGM?ref=ppx_yo2ov_dt_b_f…
