I bet that it costs hardly anything at all, because you are bearing most of the load.
I wish I had this kind of program when I was young.
For three kids I think we spend about $6K a year including books. We could seriously reduce that amount because it’s a customizable program. Some families only pay for math, English, and science classes. Some only pay for math because their parents need help teaching it. Others only send theirs to science classes because it gives the student access to labs. We have always had our kids take everything plus we have taken advantage of optional classes such as Latin, Bible Greek, Spanish, personal finance, art, etc. My two high schoolers have nine separate subjects.
Also, the program really works with those families who have a financial need. Few kids couldn’t do it because of money. I don’t know how many, but a number of them go for free.
I wish I’d had a program like this, too.