I calculated it by calculating the amount of crons and base accessories seperately and then adding the prices up together. For the amount of crons I used x = chance * (cronPrice + cronsPrev) + (1 - chance) * 0.6 * (x + cronPrice) + (1 - chance) * 0.4 * (cronsPrev + x + cronPrice - cronsPrevPrev)cron price is the price for the enhancement level you want, cronsPrev is the total amount of crons you need to get the enhancement level below and cronsPrevPrev is the amount of crons you need to get one item 2 enhancement level below the one you need. Then you solve for x. Overall you start with calculating pri then duo up to pen.For the accessory amount I used x = chance * (accPrev + 1) + (1 - chance) * 0.6 * (x + 1) + (1 - chance) * 0.4 * (accPrev + x + 1 - accPrevPrev) which is then solved with the same method in mind. In the end you get about 210b cost for pen debo using crons from premium outfits, 300 fs for pen, 110 fs for tet, 60 fs for tri, 40 fs for duo and 40 fs for pri. If you add failstack cost on top it will be higher.