An “Opportunity Grant” in North Carolina is worth up to $4200 a year to cover (or help cover) tuition at a non-public participating school.
According to the Private School Review, there are 34 private schools in North Carolina for which an Opportunity Grant could cover the entire tuition ($4200 or less).
The average cost of tuition at a private school in NC is almost $10,000. The most expensive has a tuition of over $55,000.

All 34 of those aforementioned schools are religiously affiliated schools. Over 20 of them take Opportunity Grants.
Please remember that tuition is only one of the costs. There tend to be other fees and expenses like books, supplies, transportation, costs for extracurricular activities, and food. What a voucher can’t cover, the family must fund themselves.
Currently NC is on pace to give almost a billion dollars to vouchers within the next ten years.

And this is a system that was considered the least transparent in the entire country in 2017. From the Children’s Law Clinic at Duke’s School of Law:

And still is in the 2020 version of the report from the same research team.

Here is some more food for thought from the NCSEAA, the North Carolina State Education Assistance Authority.

Again, mostly religious schools that do not have regulations on curriculum and nothing really to enforce open admission standards. In fact, in most cases, it is hard to even measure how well voucher students do academically compared to public schools which are highly regulated and very transparent. From that most recent Duke study:

Now just view the schools in the past few years that have taken the most voucher money.

And Dan Forest wants all students in North Carolina to have these.