Simple Cap Ex question

[Dave Friedman]

Hi, all. First, apologies if this is the wrong place to put this question--my buying a place hinges on it, so I hope this is the right place to post.

Anyway, total noob question. A lot of you are probably familiar with Brandon's article on estimating cap ex, where he offers ~$180/mo as a ballpark figure for SFR residences.

What I'm wondering is, how "universal" is this rule of thumb? I'm looking at buying a $60K SFR, with a rent of $790/mo.

To achieve a bare 10.2% CoC return, I need to keep cap ex and maintenance down to a monthly total of $125.

What am I missing? How does anyone buying SFRs at this price make it work if $180 is more-or-less where it's at?

Thanks so much for any thoughts--this is really preying on me.