Already has been suggested couple times now, here are the latest suggestions regarding that topic:
https://pokemonrevolution.net/forum/topic/155778-super-repel-seller/
https://pokemonrevolution.net/forum/topic/158648-add-repel-maniac
I still think Repels should stay at the same price, because they serve as a great money sink in the game. On the other hand I still would like to see Max-Repels price-performance ratio increase, so it is as efficient as super repel.