User blog comment:Dah' Blob/Some new items and changes that could be nice./@comment-1864748-20120522123801/@comment-4848673-20120524182824

After you have baught every item needed to make trinity force the rest of the gold you need is 300.

so trinity force costs 300 Plus the price of all the items needed (phage, Sheen, Zeal)

He is basically talking about all the stats that get added onto the previous items you used to build the item so its fully complete.