Basic Ideas.

Writing Pull Request Reasoning here as I found no good place to put it in the actual code. Basically All I did was set up some basic pre-idea functions to be implemented. Notice I used BigInteger's as the limits because that allows for a much bigger range of money compared to a long/float, though I may change those to BigDecimals. I added "GroupAccounts" so people can group up, and form an account. For example a faction, or a towny community, etc. Later if you all like the group account idea one could add a sort of permissions type area to them for even further customization. Note I also added in a discount class. This is either a percentage (ex: 8% off.), or a set amount off (ex: $2000 off next purchase). Then there is a limits, for example if someone doesn't pay a auction fee, or is "jailed" you can limit the amount they spend, or how much they gain, etc. Again all just ideas, and this is the start of basic ideas more for your opinions on them.