This chart shows the potential profits from rerolling Discoverer, depending on the current loot bonus roll and how many times it has already been rerolled. The profit for "Reroll to " is calculated by adding the average profit for "Reroll to " to the pure average sale price (the 12 stacks number seen at the bottom left of the chart), and subtracting both the "Reroll to " identification cost, and price of the current Discoverer based on its loot bonus. I excluded the initial identification cost since it's effectively irrelevant in the case of a high-priced item like Discoverer, although it's a relevant factor for most non-mythic items. For example, if you have a 100% loot bonus Discoverer with 4 rerolls, you can see from that chart that rerolling it to  would yield an average profit of about 2.37 stacks. I've color-coded such that green cells are a loss (don't reroll) and red cells are a profit (do reroll). The orange cells are borderline, with small enough profit/loss that I'm not confident in advising reroll/don't reroll definitively. This is of course in no way scientifically rigorous, unless there's a price checker out there who's willing to come up with confidence interval prices for every possible loot bonus value. The major assumption is that the number of rerolls won't affect the market price, which is not always the case. That said, the vast majority of people that own Discoverers are likely somewhat familiar with prices, enough to know that they're probably better off rerolling a low Disco than selling it, so it's a minimal part of the market anyway. It is assumed that the xp bonus on a Discoverer rarely if ever affects the price, so it has been ignored in this analysis. The other potential source of error is in the prices, of course. I got a general sense of the prices from @Hyco although since I ended up interpolating a lot, the prices might not be accurate (to whatever extent prices can be accurate anyway). If the prices seem particularly incorrect please let me know so I can correct them. Theoretically this analysis could be done with any item, although a larger number of IDs will tend to make it more cumbersome - Discoverer's single relevant ID and prominent market position is why I started with it. Chart: Spoiler: Large Images Edit: Salted liked this!