1.  Public schools.  The maximum tuition payments shall not exceed the receiving school administrative unit's per student cost for the preceding year as calculated by the commissioner. The school board of the sending unit may vote to pay a higher tuition rate.  

2.  Private schools.  The tuition payment to a private school shall not exceed the average per student cost in all public elementary schools in the State for the previous year as computed by the commissioner.  

3.  Debt service factor.  Notwithstanding subsection 1, beginning with the 1999-2000 school year, a school administrative unit may charge a debt service factor for newly incurred capital outlay and debt service, as defined in section 1, subsection 19‑A. The debt service factor must be an amount agreed upon by both the sending and receiving units, with the approval of the commissioner, and may not exceed 10% of a school's legal tuition rate per student in any one year. The debt service factor adjustment must be limited to a period of time not to exceed the receiving unit's repayment period for newly incurred capital outlay and debt service. The percentage of the debt service factor must be proportional to the cost of the project and the number of tuition students.