Agreed. Went back and re-read this. This does seem to be a really, really badly written piece. I personally loathe the folksy"let me explain this to you" style when discussing finances.

When we finance we choose fixed-interest ten-year loans. Taxes and insurance premiums are variables and separate. As you note, in the cited 3000 dollar example above, all three costs are bundled together as variable costs to arrive incorrectly at the 300 dollar monthly increase, when in fact only two of the three costs are subject to change. As well, as commenters are pointing out, variable costs vary state to state.

The long-term practice that works best for us over decades has been to maintain zero-percent monthly credit card debt and maintain the best possible credit rating - no missed or late payments on any loan ever.

Might be worth taking down the article, as others have suggested, until all the math has been checked. Most people I know get impatient quickly when folks don't get these kinds of numbers right. Eric might have an argument to make here, he needs to do so clearly.