How to make lightweight steel stacking shelves and the costs incurred

Assalamualaikum friends
In this video, I made a lightweight steel stacking rack with a length of 280cm and a height of 200cm with the following costs,
Material :
1. Canal C thickness 0.45
/btg,Rp 73.000,- x 8
2. Mild steel bolt,
/100bj Rp.35.000,- x 3
3. Triplex 9mm
/Lmbr, Rp.98.000,- x 2
Mild Steel Pieces:
L = 280cm X 8
L = 40cm X 20
H = 200cm X 6
Other Videos ;
/ @sahrilarda
May it be useful 🙏