If the lowest wage earner was making say 2 coppers a day, which is accurate per research, how much does a minimum wage earner in recent times make in a day (take home!)? I'd compare the two numbers as the base. Say pick a take home pay as $5/hour, 8 hours is $40. That makes a copper equal to $20 bucks. I guess that's too high a base value. I'd take a copper as $5 to be closer to a workable number. Nothing is cheaper than $5.
I wouldn't compare a typical DCC setting, which should be similar to medieval Europe, to a wealthy industrialized economy like the United States. More than half of the world's population lives on less than $2 US per day, and their lifestyles would be a better baseline for comparing the average DCC peasant.
How do people survive this way? Well, for one thing, they don't have anywhere near the material wealth that the average American enjoys. They will share a hovel or small shack with a dozen or more people, and spend most of their day outside, working in fields or mines. They will own no more than a couple of sets of clothes, and may not own any footwear at all - it is simply too expensive. Their daily diet would seem astonishingly meager to us, consisting of some beans, some rice or bread, a few fruits and vegetables, and a scrap of meat or fish on a good day. When times are tough, everybody starves, and they try to scrape together enough food so that the children, at least, have something to eat.
Tools like axes, shovels, or other daily implements are expensive and hard to come by - many people simply can't afford them. I don't know if they would represent a year's wages, but you might have to save for a few months to afford a decent tool, and that's assuming no emergencies come up requiring you to spend what little you've saved up, and that nobody comes and steals your money. Most of your trade is in the form of barter, which may be as simple as receiving a small bag of food for a day's labour. You don't have McDonald's nearby, and you probably couldn't afford to go even if you did - that restaurant is only for the very wealthy.
In many jobs, especially mining or soldiering, you may be required to supply your own equipment. Don't worry, though, because your employer happens to have some for sale, and he will simply deduct the value of your gear off of your pay for as long as you need to pay him back. Often, you will realize months later that your total pay deductions are often higher than your total pay, so while you receive food and shelter for your exertions, you will be forever indebted to your employer.
So, 1 cp = $1 is probably not too far off. Someone who is making the equivalent of $70,000 per year, in a DCC setting, is among the wealthiest 10% of people in the world (which is actually true in our modern world as well). He is almost certainly a landowner, a successful merchant, or someone engaged in a skilled profession like a physician or an engineer... which, coincidentally, can only ever be pursued by people from wealthy families, because they are the only ones with the money and connections to send their children for the training.
Those of us who live in Canada, the US, Japan or most of Western Europe have a pretty skewed view of what a "typical" lifestyle is. In some ways, the global economy isn't much different than it was in the middle ages; globalization has simply allowed the wealthy elite to live in different countries from most of the desperately poor peasants whose labours support, or at least don't interfere with, our relatively comfortable lifestyles.
Another way to think of it is that every appliance and electronic device you own today would have been, in medieval Europe, a servant or animal in your household. If you can afford a car, a refrigerator, or a vacuum cleaner, then your economic position is comparable to someone who was wealthy enough to have hirelings and servants in medieval Europe.