The $25 first aid kit is a basic foundation for all first aid kits. It's appropriate for minor wounds for 1-2 people, maybe as many as 4 if you're diligent in keeping it stocked.
So, what can you possibly get for a mere $25? A fair bit, though to be honest, we'll end up having enough supplies to make at least two kits from most of this.
Alcohol prep pads. Basic for wound cleaning, plus they're real handy for firestarting. (Hey, multifunctional is always better, no?) $3.19/200
Nitrile Gloves. Keep the patient's blood and other fluids separate from your own. Critical to prevent the spread of a whole host of nasty infections. I prefer nitrile to latex because it's far tougher, and has fewer allergy issues. $3.99/40
3x3 Gauze Pads. 3x3 is a good size for gauze pads. It's big enough to cover most minor wounds, but not so big as to be sloppy and cumbersome. (In the next steps, some bigger pads will get added.) $6.29/25
Tape. I like mine waterproof. It sucks when your bandage keeps slipping off, and getting things into wounds is a guarantee for slower healing. $3.99/roll
Adhesive Bandages. These and these cover most basic cuts and scrapes fairly well. $2.79 and $2.99/box.
Tweezers. Handy for pulling slivers, stingers, etc. So inexpensive as to be a gimme. $.79
Ibuprofen. Probably the most reached-for thing in my kit. Pain sucks, mitigating it is very nice. $2.99
Grand total: $26.23. A hair over my budget, but pretty stinking close. You could probably beat my pricing by shopping around. I hit my local Walgreens for supplies, though, just out of preference for hitting local brick-and-mortar shops. You can pack it into virtually any handy pouch or bag, and Walgreens happens to be giving away a decent little first-aid bag if you buy 3 or more first aid items there.
Nice-to's: If you've got a couple extra bucks floating around, here's a pair of add-ons that make a big improvement to your kit.
Rolled Gauze. Used to hold those 3x3 pads, for splinting, and a whole mess of other things. It's kinda like first aid paracord. I like the 4" width, it has more versatility than 2" or 3" rolls. $8.99/5 rolls
First aid scissors. Blunted tips to slide under bandages and clothing without cutting skin, and aggressive blades to cut thick material. Very handy. $5.99
Next week, we'll expand the kit to $50 and get into some really solid territory.