WTFBrutus

I like to have a large number of fast-moving but weak zombies. I want them to be everywhere, but I want to be able to kill them with a couple swings of a bat.

I think the best safe house is right in the middle of town. I like the two story office building next to the big church. There's a balcony that's good for farming, several bathrooms to at least get you a few days more of water after it shuts off, and plenty of windows to board up to level your carpentry. Honestly, at this point in the game's development, a house that would be "safe" in real life (like the picnic area or the ones at the edge of town) is pretty much the worst place to build, because you won't have anything to do once it's built.

OP is saying you should be able to fill the bathtub with water from any bottles, etc that you are carrying. So, for example, you could go from house to house and take all the leftover water from sinks/toilets/tubs, then bring it home and put it in your tub. Alternatively, you could use it as a backup to rain collector barrels. So you move the water from the barrel to the tub.

Second the garbage bags. They are super light-weight, and they run out fast once you actually need them. They are one of my "always grab" items, along with sand bags (which I empty out), nails, and, well, many other things. Another thing I do is just keep a piece of paper next to me and write down the skill books I've collected. Simple, and maybe a little unnecessary (it's not like they weigh much) but it keeps me from getting tons of copies of the same books that I haven't read yet because I can't remember that I already have one, because I have the memory of a goldfish. I also always have a hammer and nails in my bag to repair my baseball bats.