system gives each user the same amount of points to buy ships and upgrades
user purchases as many ships of different types as they would like
a. user cannot purchase a ship if they cannot afford it
user can customize the equipment on each ship
a. system denies upgrade
user does not have enough points
user needs to have the system in order to upgrade (ie. cannot buy shield recharge rate upgrade if ship is not fitted with a shield)
b. system applies upgrade to ship