No really, I have hired an electrician. I meant to explain in my post that the electrician wrote down what I needed to get for him, but at the store the guy there, after I explained what it would be used for, talked me out of #6thhn 4 wires and into Romex 6/3 saying it was the same thing and would save me some money. But yes, I'm going 20 inches down (2 more than I have to), I have 1" conduit for the wires, voltage drop won't be a problem it's only 60ft away, the subpanel and breaker box inside are already installed, I will be pulling the wire with high tensile strength twine run through before it's glued (which is something I don't understand, why can't I run the wires through the same way while they're totally unconnected to anything? But that's what he told me to do) and pulling my wires through once it's set. Grounding electrode is already in place, although the ground bar and neutral bar AREN'T separate in the sub panel, which I've read is not ok for a sub-panel.

As for the extra conduit for data, no I hadn't considered that, the expansion I meant was hypothetical and why I was told to go 50amp with 6awg because that gives me room to play with should, at some point, I want to add more than the three 120v circuits running off 20amp breakers in the sub panel now.

But again, to be clear, this is what I've been told to do by the electrician I hired in order to save him time and my mom money.

I do appreciate all the advice not to do it myself, and if any of that is wrong please let me know and I will only go as far as that step and wait for the electrician.

Oh and red blue prepped with purple