Reply by LeeRoyMan

You do have a limited budget, but it is doable if you want to make some sacrifices.

I would use 3/4” woodgrain melamine for the uprights and shelves.
2 1/2 – 3” wide 3/4” hardwood for the faces of the uprights. 1 1/4” – 1 1/2” wide for the shelves.
Your choice of species to be cost effective, I would use alder.
I would groove the back of the faces for the melamine uprights to go into.

I agree that in each section you need to fix the upper and lower shelves.
On the fixed shelves I would attach backrails to screw the unit to the wall.