Tycoon is a NPC who gives a sidequest in Newisle. In order to do his sidequest it costs 5000.
The sidequest is intentionally difficult. You will need lots of bullets to complete it.
Once you have finished the sidequest, Tycoon gives the player the ability to attempt to take over a property. A takeover attempt costs 500 and this is given to the owner of the property you are attempting to overrun.
To take over a property from another player, you can do one of two things. Firstly, kill that player. Secondly, run the particular quest as given by Tycoon in order to take over the property.
The quest is nearly always to either kill a mini boss at the location of the business or to kill the actual player owner of the business