9dcabf3c74e23006 Take a look at this thread:
Cheapest way to own compilation/sets/venues! | EA Forums - 1857088
Search for oh my goth , or just scroll down, and you'll see the cheapest way to acquire it if you own nothing from it already. But you do own the Multi-Tab, so you're partway there. The next questions, it looks like, are how many items you own from Technophobe No More and the May 2012 compilation, or rather how many points those items are worth at full price. That determines whether you can buy either of the two sets at a cheaper price than Oh My Goth, which does not go on sale but has enough overlap with May 2012 that if you own the latter, the former is free.
I'm not suggesting you buy the items listed in the link above, only that it's a good way to get a sense of how you might proceed here. For what you own, there may be a better path.
What I do in these situations is I add up the points of the items I own in a set and compare them to the lowest sale price of the set. If the points from the items I own are higher than the sale price, the set will be free for me when it goes on that sale. Otherwise, I would pay 90% of the difference when the set is on sale, i.e. if my items are 100 points short of that lowest sale price, I'd pay 90 points to complete the set. Then I can look at the items I don't own in the set and see whether any of them are on sale at any point; if they are, I can buy enough to lower or erase the gap between what I own and the sale price.
If you want more specific help, let me know what you own in these sets (you don't need to link; just a list will do), and I can compare it to the available Daily Deal sales.