Monthly, but the price isn't quite as cheap once you consider that the apartments he's looking at are 1LDK at best, or in western terms, studio apartments. If you step outside the high-demand cities, such an apartment in America would only cost $500~700/month and I've seen some listings go as low as $250 for a decent sized 1LDK out in the suburbs.
Umm...i think you might be confusing apartments. I think he's looking for a 1K/DK...or at least, last one was a 1K i think
A 1LDK is basically a big apartment, counting: 1 bedroom, a living/dining room and a separate kitchen....basically a 3 room apartment....and renting it for 700 should not be possible. A studio apartment, if wikipedia is right, is equivalent to a 1R where it's a single room (duh) where there's the kitchen, the bed and an inexistent "open" space.
Now, idk about prices elsewhere, but here, for 6-700, you only get a 2 room apartment...which is a 1K/1DK
Anyway, the differences are explained more or less here: