I would be looking at the used market for sure.
A quick look in kijiji shows lots of older hardtails with vg components and owners who claim limited use. Older bikes are hard to sell, but they are often in great shape with motivated sellers. But, you have to know your way around a bike or be willing to put in the time to learn. Park Tools has great instructional vids.
In the Calgary bike sale that was suggested, I'd be looking at that Kona Caldera. The were a great bike with solid components. You never know about the condition, but it could be a real gem.
Example of a kijiji bike that could be awsome. Norco Charger.... $350.
https://www.kijiji.ca/v-mountain-bik...4768?undefined