And now get out your magnifying glass. We're on the look out for the fine print. Let's see what's on the radio. 300 vehicles must be disposed of in three short days! Did you get that? Reporter: We... See More
And now get out your magnifying glass. We're on the look out for the fine print. Let's see what's on the radio. 300 vehicles must be disposed of in three short days! Did you get that? Reporter: We couldn't understand that car commercial either. Half of it was completely -- I couldn't hear it. Reporter: And neither, as it turns out, could a lot of people. You got all that, right? No, I did not. Reporter: Not when the words are going by so fast. Any of it? No. Reporter: You see, we are in the midst of a social experiment. Could anyone figure out what was said in the disclaimers in the radio ad? You couldn't understand any word? No. Reporter: You've heard of fine print before, right? It comes in print, televisions and radio. Something about tax, title and license. That's what you got out of it? Yes. Reporter: Which brings us why we're doing this, there are certain things you need to be on the look out for. Why does it matter? Let's listen to the ad again this time much slower. Over10,000 per year, 25 cents per mile. He's saying it will cost 25 cents per mile if you expand the lease. One example of why the details could cost you big bucks. We were curious who could even talk that fast. Have you always been a fast talker? Yes. Reporter: Turns out this guy can. Will you read anything they tell you? Pretty much within reason, yeah. Reporter: Meet kenny, he's the voice of car dealer spots.Com which produces hundreds of radio ads for car dealers each year. When it's so fast do you think it's meant to be understood? No. They're trying to get in the phone details without you noticing them. It really is the fine print just by making it faster? Exactly. Reporter: Dealers give him a script and a time limit and his job is to fit everything in however he can. You can say look it's impossible to read that in 30 seconds and they say, well, can you try. I'm a competitive person. Go. Stock number -- Reporter: I tried my best but it wasn't easy. See dealer for details. 11 seconds. Reporter: Even as fast as kenny reads, we would shocked when he revealed that his voice is sometimes electronically sped up even more, making it even harder to understand. Of course, it's not just what you can't hear. It's also what you don't see. You can't take a headline that promises a and then in the fine print say we were just kidding. Reporter: This is edgar. He's obsessed with what he calls mouse print. In fact, it's the name of his website. They try to paint the roseyest picture they can in the headline and put the truth in the fine print. Lose 50, 88, 45 pounds. Look at the bow flex ad, want to lose weight, no problem. Walking, surely anyone can do that. Did you catch it? See these words down below, participants followed the meal plan. It drops your intake to 1300 calories a day for men and a measly 1,000 calories a day for women. So much for just walking. Still the results seem impressive. I lost 73 pounds. Reporter: Don't drop the glasses just yet. Look here, average weight loss, only 17.4 pounds. So another thing to be on the look out for in the fine print. Clues that it's not so easy. Bow flex told us those success stories are from real people and they send those diet details to buyers once they ship out the bow flex. This mir lax ad seems easy to follow. See that tiny little writing? It could take up to three days to work. That's an awful lot of waiting in order to finally feel great. They told us the messages consumers shouldn't wait to take their pill once their symptoms appear and that they haven't received complaints from consumers about the tag line. Next fine print folly to look out for? It's call it the up to. Almost 40% of consumers are blind to the word up to. They see save 80%. That's the big sale claim on the cover of this catalog. Seems like huge savings. Take a closer look, a little closer, see it? Up to 80%. We barely noticed it. So we went back to the people in the park. They are saying that you can save how much? 80%. Reporter: And asked everyone to search for those tiny words. But people still couldn't find it. That's when we pulled out our trusty magnifying glass. Still don't see anything. Is that clearer to you? Is that like an equals sign? I'm not sure that what is. Save up to 80%. There we go. I thought that was dirt. I couldn't even see it. Reporter: Lower down the ad does disclose lesser savings as well as regular and sale prices to would allow you to do the math yourself. Finally, beware the everything but headline. This macy's ad promises big savings store wide plus an extra 20% off. Look there in that tiny type, exclusions including selected departments. How bad would that be. We were curious so then we called macy's and this was the license department. Reporter: That's 114 exclusions. American icon, american rag. Carlos, citizens -- Reporter: Off of a supposedly store wide sale. Macy's told us they continually try to make things clear about what's on sale and what isn't as they don't want to disappoint their customers. Our experts say you need to read the tiny words. Studies show many people don't. If you feel misled, raise a fuss about it. Tell the store about it and then complain to a government official. If it offer seems too good to be true, it probably is. Reporter: Remember this dad's words of wisdom. Always read the fine print, right? Is that what you learned? Yeah.
This transcript has been automatically generated and may not be 100% accurate.