I want to find a phrase (or a slogan) to indicate that an aitical is sold at a price that's the same with the amount on the price tag.

Could I say "something is sold at distinctly labelled price", or is it appropriate?

How about "no-kidding price"?

Emotion: stick out tongue
Priced as marked.

Is there a "sale" going on so that the prices on the tag show the sale price, but people are wondering if there is another 20% off from the price on the tab? I'm wondering why people wouldn't asuume that the price was correct on the tag?
"Priced as market" is good, thanks!

No, it's the opposite, It assures the customers that they won't get ripped off, in the event that some cusotmers are not familiar with the products, and have no idea of the range of the price.:-)
Students: Are you brave enough to let our tutors analyse your pronunciation?
As marked, not market. But perhaps you mis-typed it?
Thanks for your correction. It's a typo.
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What I see here is:

Regular price: $2.00
Sale price/Special price: $1.00