what are your best tips for a household?

we've moved from one house to the next, but are deciding to stay put finally. Finally have some room to store some diy bulk soap and dry goods. with that in mind I'm betting there's some other ways to be frugal I've been overlooking, but have available to me now. (like getting rain barrels, or weighing the cost of solar panels)

what other tips do you have? looking for the most bang for my buck long term investments.

just for more detail, we have no children and don't plan on it. we've trained our cats to use a toilet so we don't have to pay for kitty litter