Note that if you collect interest 30 times without withdrawing, your starting capital gets multiplied by well over 200. And although it looks as if it's always rounded down, the amount in the bank is actually a floating point number. So it works as expected even if you start with a single LC. (Then it just takes several days until you see the first indication of growth.) Therefore, if you put just 1 LC in the bank and collect interest at the same time every day, it takes only 2 months to get 200 x 200 = 40,000, the price of Prestige 4. If you start with 200 LC it just takes a month, and if you also add a few LC from posts on most days, it's even faster.