Since I started home brewing, I've not bought a single bottle (or Guinness can) of beer. If I'm out, then I just wait until one of the batches is ready. I'm trying to make my pipeline so that I never run out before another batch is ready... I do cut it close sometimes though.
Not counting when I go out, which is about once a week, I get about 1 a month for myself (a man has to do research right?). However I do buy probably 2 cases of Miller Lite for my wife. She's very calorie conscious and will only drink one of my beers a day usually. If I brew a smaller beer with less than 140 calories she'll drink more. When I do go out I probably drink 6 so maybe I'm more 5+ I guess.
I like to try different craft beers to see what I want to brew next. I buy more 22oz bombers than anything. Usually 4-5 every Friday. It's good to taste new things and I like to bottle in all 22's. Just finished a Left Hand Tripel.
0 since I got my kit in October. I lied, 2 cases of Magic Hat Dark As Night Lager because they were $12.50/case and that's cheaper than buying new empty bottles at the LHBS.