By death 3 I could end up with rank 5 or 6 merchant and by death 4 I can have Penny Pincher...
At rank 3 I can Sell potions for what I pay for them. At that point buy all I can (After selling everything I own, sell them, buy again, wash, rinse repeat) and save (to see progress) die see how far it ranks up, reload if not maxed, or continue playing if it is.