Basement stairs for bungalow - Are prefabricated ones cheaper?

Since a basement is planned for the bungalow, but everything is still in the consideration phase, I am asking here. The interior staircase should be functional and affordable, accessible through a door. Are the prefabricated stair parts still available for purchase? Acquaintances only made an outdoor staircase, which I find too economical.

Why shouldn't there be prefabricated stair parts available for purchase? You simply take what is also used outdoors or have it delivered prefabricated accordingly. Where should the problem lie?

Of course, you can also concrete something like that on site or have it built by a locksmith or carpenter.

The cheapest option is certainly to use a simple ladder.

I find it quite interesting that your acquaintances only have an outdoor staircase when they have to go to the basement in below zero temperatures or in snow and ice. How can anyone come up with that idea?

All in all, your architect can tell you more about that.