Advice before buying gaming laptop

In a few weeks I'm going to visit a store where they recently started selling gaming laptops, consoles and stuff (they used to only sell phones and things like that). The prices of some mid-high/high-end products are absurdly low. I'm a little skeptical about the prices, but if I go in person I might be able to try the products. They say they come newin their box and I can see the specifications match the manuals for those products.

What would you recommend I should look at on the computer to make sure it is not a scam, when trying it in person? I think I could check the laptop hardware ID to verify if it matches the box, but what else could I do?

I noticed that some of their laptops had a Japanese keyboard, should I be worried about that? Is there any crucial difference or anything I should know if it is a Japanese product?