i have a small memo book. Ive went thru each room and wrote in this pad, measurement of room, windows, how many and measurements, closet door, light switchs and plug ins. Not ever set is standard, so always take note. Size of hallway doors to bathrooms/bdrms etc, size of shower/baths, and note light fixtures also, one bulb, 2 bulbs, or size of ceiling fan. I keep that pad in a box, along with a seamers tape measure, batteries of all sizes, a pen and calculator. This way i can test items that require batteries, and measure items and compare in my book. Alot of people when upgrading thier items, thier older items they sell may be appealing to you, such as a set of shower doors for example, or blades for ceiling fan, or new light cover for one, etc. You can buy everything i listed at the dollar tree all for about ten dollars. In the long run, you will save that and more, especially, when you see a little handheld game for 2 bucks, want it, but not sure if it works? waste of 2 dollars if you dont test it first. other items for household, u know whether it is right for you or not if you keep your measurements with you. Such as Drapes, for example, wether it will cover your window span, or if they are long enough or too long, etc. I buy 8 packs of batteries for one dollar at the dollar tree, has saved me a few times from a bad purchase.