Final Fantasy XIV. Should I buy latest expansion only, or complete experience? Difference is 20 bucks. Does new expac include old content?

You should buy the Complete Experience, IF you do not have the game already.

The Expansion is not like the Guild Wars Faction or Nightfall, in which they are seperate stories and you do not need the Original or the Other side. It is a Item in which extends the story the level, and the powers given in the Original Game. Hence the Term Exapnsion as it Expands on the Original Content.

You can have Final Fantasy 14, and not play the Expansion, but if you can't buy the Expansion and play the oroignal game. That is like buying a costume DLC for a game you nevver played or bought.

So if you do not have FFXIV, then Buy the Complete Experience.

You can't buy the expansion by itself. You need the base game.You actually can't access any of the expansion areas without completing the main story for A Realm Reborn, which means doing every story quest from the original 2.0 content to the 2.55 quests leading into Heavensward.

So you either need to buy just A Realm Reborn or the complete experience with has both the base game and expansion if you want to start playing.