Hi, I am kinda new here but here goes.
I recently bought a used Canon 7D (original) for around $300 for my son. A Canon 10-22 can be had for around $200. Not a bad setup for landscapes and close to your budget.
If they wanted to add a decent to fair midrange zoom the older Tamron 28-75 f2.8 is kind of a bargain sleeper lens.
These lenses are not of course up to Canon L glass standards but do produce nice images at very reasonable cost.