As far as reusable trolley bags go, you'll struggle to find them cheaper than this! These green clip-on bags are eco-friendly and designed for constant use. Get them for as low as $4.88 each right now on eBay
Bags like this are so much more convenient than your regular Eco shopping bags because you can actually clip them to the trolley, for super easy packing and sorting.
Each of these tough bags holds about 18 kilograms, so you can really load them up. Also, they fold down flat when not in use, so they won't take up much space in the boot of the car.
You can wipe these down with a damp cloth when needed, and there's also a side pocket for your phone or receipts.
Note, this product comes from China, and will probably take a few weeks to arrive. If you'd rather order from an Australian seller and get your bags quicker, the best price we found is $6.64 (with $2.70 shipping) from this seller.
These bags ship FREE.