We had a HELOC available, but didn’t touch it til I was unable to work after a major medical event. My income covered about half of EFC (seven years ago), and we tapped in HELOC for about 1/3 of a year’s COA. Helped that S1 was graduating just as I had my medical event – those funds went to S2’s last two years.
We won’t be funding grad school – if S1 goes, it will be employer-paid or fully funded; S2 hopes to find an employer who will help pay while he works. That was part of the trade-off for private vs. public.