Buy ranks with ingame money
If you want to sell ranks with this plugin, you need an economy plugin like iConomy or BOSEeconomy. If you want to sell a rank, you have to add it to the config like this:
Ranks: - Example,10.0 - Admin,999999.0
Any player with the permission 'MasterPromote.rank.buy.Example' would be able to buy the rank Example for 10.0 dollor/coins/whatever. If he bought the rank, he gets promotet directly after he used the command. To buy a rank, just type /buyrank [rank]. To see a list off all ranks, type /ranks. You need the permission 'MasterPromote.rank.list' to see the list.