private IEnumerable <IPurchasable> GetPurchasableEquipment()
        {
            List <IPurchasable> purchasableItems = new List <IPurchasable>
            {
                agentFactory.CreateSnackMachine(TimeSpan.Zero),
                agentFactory.CreateSodaMachine(TimeSpan.Zero),
                agentFactory.CreateWaterFountain(TimeSpan.Zero),
                agentFactory.CreateOfficeDesk(TimeSpan.Zero),
                agentFactory.CreateTrashBin(TimeSpan.Zero),
                agentFactory.CreateSnackMachine(TimeSpan.Zero),
                agentFactory.CreateSodaMachine(TimeSpan.Zero),
                agentFactory.CreateWaterFountain(TimeSpan.Zero),
                agentFactory.CreateOfficeDesk(TimeSpan.Zero),
                agentFactory.CreateTrashBin(TimeSpan.Zero),
                agentFactory.CreateSodaMachine(TimeSpan.Zero),
                agentFactory.CreateWaterFountain(TimeSpan.Zero)
            };

            return(purchasableItems);
        }