(Another repost, this time from a post I made on The Rally Point. Just want to get things going here. I plan to go into more depth on many of these items.)
Not everyone can afford expensive, top of the line gear. Folks just started in their careers or those on low incomes should be prepared for emergencies, too. While the ability to buy lots of expensive gear and food is definitely an advantage, there are plenty of things a family with less money can do to help themselves weather an emergency.
Buying food in bulk is a good way to lower costs. Look for sales and buy flats of canned goods, then rotate them in and out of your daily usage. You don't need fancy containers for water storage. Used 2L and 3L soda bottles work very well, after they've been thoroughly cleaned and filled with tap water. Put a couple of drops of bleach in each bottle and store them in a cool, dark place. Inspect every 6 months to a year, drain, clean, and refill.
Get a cooler to help preserve perishables if the power goes out. Use perishables before canned or dried foods if that happens.
Most people have barbecue grills, which can be used for cooking if the SHTF. Have extra propane or charcoal on hand. Sterno or alcohol stoves made from soda cans can be used to heat food, too. (Google for "pepsi can stove.") Even a coffee can, can make a good stove. (Google for "hobo stove.")
Extra emergency clothes and blankets can be picked up at thrift shops or from military surplus dealers. In a pinch, contractor weight plastic garbage bags can be slit to make a tarp or a poncho.
Have a couple rolls of duct tape on hand. This is one item where it pays to not buy the cheapest you find. It can be used for repairing everything to cars, stuff around the house, and even a temporary bandage. Baling wire is good stuff, too.
Have basic hand tools, nails, drywall screws, string, and if possible a rechargeable cordless drill with screwdriver bits.
Surefure flashlights are cool but they and their batteries are expensive. A two D-Cell flashlight will provide usable lighting in an emergency and they're cheap. Mini Maglites can be picked up for $10 and are light and compact. With a $5 LED conversion head from Nite-Ize at WalMart, they run much longer and give out more light. Don't forget spare batteries.
When used carefully candles are a useful yet inexpensive adjunct to your emergency lighting supplies.
Budget communications are available, too. Obviously the first thing to try is your landline. If that's out a pre-paid cell phone may work, but if the landlines are down so too may be the cell towers, especially if you've just been through a hurricane.
Wireless communications can be in the form of a CB or FRS/GMRS radio. CBs are common and work fine for local communications. If possible, get one that can also receive National Weather Service Wx broadcasts. For example, I have a Midland CB walkie talkie with a cigarette light adapter and magnet mount antenna in my truck. I can use it on foot or in the vehicle, and receive Wx warnings. CBs will also be good for communicating with truckers delivering relief supplies.
If you can spare about a hundred dollars and some time, you can afford to get a Technician level amatuer radio ("ham") license and a used 2 Meter FM handie talkie. Compared to CB, FRS, or GMRS, a ham radio greatly improves your commo capabilities in a SHTF situation.
Sanitation is very important, especially when normal systems are disrupted. A 5 gallon bucket (at most a few bucks at Home Depot) and plastic bags can make an expedient toilet. If necessary a hole can be dug to dispose of waste.
Unfortunately, while emergencies often bring out the best in people, they also bring the worst in others. Therefore, the prudent person will have tools for protection. One's arsenal need not be fancy nor expensive to provide good protection.
My first choice for a budget SHTF arsenal would consist of an SKS and a 4" Ruger Police Service Six, preferably in stainless. Both are extremely rugged and reliable, ammo is reasonably common and not too expensive. Total cost for both guns should be under $400.
If a semiauto rifle isn't an option than second choice IMO would be a used Marlin or Winchester levergun in .30-30.
You obviously want a rifle because it is the most effective weapon for self defense. Shotguns are formidable at close range but ammo is bulky and heavy, and recoil is stout.
The rifle should be equipped with a sling. You don't need a fancy "tactictal" sling, a carry strap will do. There will be instances when you'll need both hands but putting the rifle down is unwise.
Ammo for the SKS can be carried in clips in a Chicom chest pouch, a belt pouch, or in surplus 5.56MM bandoleers. If you get a .30-30 instead, get a butt cuff for some onboard ammo and a belt pouch or belt slide with cartridge loops.
You should have handgun in case you need a portable, concealable weapon. E.g., when you have LEOs who think that the serfs should be disarmed, as in New Orleans post-Katrina.
The handgun needs a holster and sturdy belt to support it. Also some means of carrying a couple reloads, preferably speed loaders in belt pouches. Bianchi Speed Strips are a viable option, especially when you need to carry concealed, because they are flat.
Since for the sake of this topic budget is a concern, a milsurp cleaning kit with a sectional rod and a .30 caliber and 9mm sized bore brushes/jags will allow you to perform preventive maintenance. Cleaning supplies don't need to be fancy, just need some patches cut from an old T-shirt and a CLP. Automatic transmission fluid works quite well and is cheap.
Let's hear some other ideas for emergency preps on a budget.