To only allow some specific people to register into the price type from online registration, you can set a registration password for the price type, only people who entered correct password can register it. 

Below are the steps to add password to registration categories at Registration Categories
  1. Open Your Event after Logging into ACTIVEWorks Endurance
  2. Click Setup
  3. Click Registration categories
  4. Locate desired registration price type
  5. Click Edit next to Price restrictions
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  1. Type in Registration password
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  1. Click Save
Note: After a password is added to price type, it shows up online as below:
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