I rarely drink bottled water. Frankly, I don't trust most of it. I have a Zero Water pitcher and filter I run the city water through. It filters 99% of the contaminants, including lead, found in the water. It also filters out 99% of that nasty-tasting chlorine.
Not unless I forget to take my reusable water bottle with me when I leave the house. If I get really thirsty, I'll but a bottle of water, but I try not to contribute to the amount of plastic smothering the planet already.
Yes, about four bottles per day, or a half gallon. Sometimes I buy the gallons because they are easier to carry into the house; I also prefer drinking from glass. I do not own a mug, cup, or glass that is made of plastic.