The cost of an electric cable is mainly determined by the cost of the metal used in the design,

The cost of an electric cable is mainly determined by the cost of the metal used in the design, the permissible value of the electrical resistance of the cable at a given …

Specific electrical resistance of copper = 0.0175 Ohm * mm ^ 2 / m, and aluminum = 0.028 Ohm * mm ^ 2 / m.
Home appliances are now used in apartments with a maximum of 10A, we will take a little with a margin. For 15A wire diameter: copper 0.32mm, aluminum 0.4mm.
So the resistance of 1m of copper wire = 0.0175 Ohm * mm ^ 2 / m * 1m / 3.14 * (0.5 * 0.32mm) ^ 2 = 0.218 Ohm.
Aluminum wire = 0.028 Ohm * mm ^ 2 / m * 1m / 3.14 * (0.5 * 0.4mm) ^ 2 = 0.223 Ohm.
The cost of 1m of copper wire = 170 r / kg * 8.92 g / cm ^ 3 * 1m * 3.14 * (0.5 * 0.32mm) ^ 2 = 0.122r.
Aluminum wire = 60 r / kg * 2.7 g / cm ^ 3 * 1m * 3.14 * (0.5 * 0.4mm) ^ 2 = 0.02r
Conclusion: for better energy supply to the apartment, it is better to use copper (since there is less cable resistance), but for financial savings it is better to use aluminum.