Card selling

Idk if you'll like this idea or not but can we get an option to trade tower cards for 85% of their cost. Like to transmute its upswipe, we could add downswipe to sell the card for some % of its value... I feel 85% could be nice but it's upto you how much % should be kept. What do you think of this idea??? To add scalability and avoid its abuse we can add a diminishing returns system along with % based on tower rarity. For example : 90% of cost - Common towers 85% of cost - Uncommon towers 80% of cost - Rare towers 70% of cost - Unique tower 60% of cost - Legendary towers This is just tentative number... As i said its all upto you to decide %. Now about diminishing return we can add mechanism like after every 10 (or any suitable number) sells the rate decreases by 1 or 2%... So after selling that many common cards the rate drops to 89% of cost... And maximum depreciation of cost can be 15% so after lots of selling common cards will give only 75% of their worth. We can change this number according to card rarity and drop chances with special rules for unique and legendary cards. TL:DR version: Add a downswipe feature to sell a card at certain rate of its face value depending on rarity. More you sell the lesser returns you get.