Let's see.. Started with a ego-t starter kit for around $110 this past February and bought too many different liquids, cartomizers, tanks, atomizers the first couple of months.
Around early summer, I shorted both my batteries that came with the kit in my first attempt at rebuilding (vivi nova)
Bought two replacement 1100 mah ego-c twists for about $30 each but got better at rebuilding and have only needed to buy liquid monthly now for about $25 a month.
One of those batteries just died on me a few days ago so I just ordered a SS Vamo ($43.50), Xstar charger ($20), 2 hybrid panasonic 18650s ($12 each) and a Terminator R/A ($60).
Honestly I don't mind how much I'm spending on ecig stuff. Was spending around $200 bucks a month when I was smoking analogs, and even if I were to spend more on e-cigs, I tell myself its a pretty fun and addicting hobby =)