That is hard for sure buying single cards lets you get your deck leveled up cheaper. But it is fun to chase 1 pack magic because if just one of your 20 packs has a Gold Foil Legendary then it pays for those packs. Yet I get not chasing that when you don't have the funds to try 20 packs say 5 times. So targetting the market is the way to go to ensure you get a good level deck on the cheap.