EDC: Every Day Carry. It's a big topic of discussion amongst survivalist types. Here's what I usually carry, tool-wise, while working at Casa Giardino di REDACTED:
What's not shown is the first-aid kit and Channel Lock fence pliers that's always in my working tool bag, but I don't consider them EDC since they're not on my person.
Since I'm a commo guy, we'll talk about the radio first. They are middle-of-the-line Cobra FRS/GMRS radios. I think cost $50-$60 a pair, including rechargeable batteries and a nice drop-in charger, at the local Wal-Mart. They work well, are unobtrusive on the belt, have been proven to be rugged and reliable, and won't make me cry if they get dropped in the mud and stomped to death by livestock. As a bonus, they have NOAA weather alert (very useful out here in Wyoming), and will also charge off of standard USB-type phone/device chargers. Their RF power output is more than adequate for talking around the farm, and the batteries last all day long provided one is not too verbose. They accomplish their intended function.
The top right knife is a $10 special (on clearance) from Tractor Supply. I've used it heavily for a few years now, and have yet to find fault with it. It's an assisted-opening liner lock, which happens to be my second-favorite locking mechanism behind Benchmade's Axis-Lock. This is another working beater that can be easily and inexpensively replaced at any hardware or ag store. I'm of two minds regarding the half-serrations on the blade. Depending on the cutting task they are either a significant boon, or a pain in the neck. Usually I find them to be more useful than not. Figure out what works best for your situation and go with it.
Finally, there is the humble Victorinox Super Tinker Swiss Army Knife. This replaced a Leatherman Wave that I carried for many years. It's lighter, less obtrusive, and has proven to be more handy on the farm than the Leatherman. It's also a quarter to a third of the cost of the Leatherman. The most commonly used tools on it are the small knife blade and scissors, followed by the screwdrivers. Like any other pocket knife/multi-tool, the screwdriver's are "adequate", and given my preference I'd rather use a real screwdriver. However, if I'm caught with having to fix or adjust something right then and there, it's handy.
These are real-life work tools that see regular use every day on a farm. So far they have proven to get the job done. The reality of self-sufficient living is that you'll be maintaining, fixing, and quite likely fabricating things around your homestead. You'll need things that will work reliably, and are affordable.
Note I didn't talk about working guns here on the farm, because a) It should be the topic of another post, and b) I'm not ready to deal with that level of gayfishery in the comments section.