Depends on which category your are in and if you do one day or two. If you have not done and HPDE before or have good track experience, you will be in HPDE1 which is a great learning experience. The can teach you a lot.

1 day (either) HPDE2-4 - $249
2 day HPDE2-4 - $369
1 day HPDE1 - $289 inludes instructor

There is not discount for 2 day HPDE1

https://www.nasaproracing.com/nasa_e.../?event_id=405