Instant Selling

Instant Selling of Pokemon is the instantaneous retrieval of Platinum coins when selling a Pokemon, rather than waiting for other players to buy them.

Because there is no player on the other end of Instant Selling to obtain the Pokemon, Instant Selling is synonymous to deleting a Pokemon for money.

In other words, Pokemon that have been Instant Sold are gone forever and unretrievable.

Navigation
The option to Instant Sell can be found in the bottom category, "Money/Shops," of the right column.

Money
Instant Selling Pokemon grants a set amount of Platinum Coins in proportion to the level of the sold Pokemon (with variance.) It is usually less than what many players would be willing to pay for, meaning your net profit goes down.

A level 1 Pokemon will sell for approximately $350.

A level 10 Pokemon will sell for approximately $1,000.

A level 100 Pokemon will sell for approximately $20,000.

Ungendered Pokemon Instant Sell for more Platinum Coins.

Other factors, such as the amount of that Pokemon in game and whether or not it is legendary, do not seem to affect the sale price.