How does trading work?
Special trades are unregistered, shiny or Legendary Pokemon.
The amount of stardust depends on your friendship level and what you are trading it can be between 100- 1,000,000 stardust.
You can find the exact value of the trade you want to do with a quick search.
For shiny Pokemon that is new:
- Good - 1,000,00
- Great - 800,000
- Ultra - 80,000
- Best - 40,000
The only time they have allowed multiply special trade in one day is if you are at a go fest.