https://repl.it/@DaadAd/capeshoespricecheck I created this awhile back to be able to estimate the price of an attack gear with slots. Basically, the calculator takes into account all the possible attack stat the item could end up as and based on the price of those attack, it can calculate the average price of the item. I didn't release this into the wild obviously because this information is useful to make money but I'm quitting so here's an early christmas present to you guys. The accuracy of the calculator also depends on your awareness of gear prices which this program may or may not be correct. ( you can fork it and edit it)
posting additional info That is the case for 1 slot. It gets way more complicated with more slots and becomes impossible to humanly calculate the probability with more slots so the calculator helps in that. I don't play anymore so you have to update the actual prices in the code itself for the calculator to output relevant prices. The calculator is useful for answering questions like, should I scroll my 10att 3slot shoe or should I sell it for 14b (for example). If the calculator determines the utility (price) of the shoe to be >14b, it basically means that if you have many many 10att 3slot shoes and you scrolled all of them, on average you would make more than selling them for 14b each. Do note that you are still likely to lose money from cs-ing (6/11 the att stays the same or is reduced and 100% of the time the slot is wasted), it is just that if you do hit the jackpot (getting a positive increase in attack), the returns are sometimes big enough to justify the risk.