Don't be fooled by all the talk of multi-million-dollar sales at 15 Central Park West and the Plaza. Take those out of the equation and the Manhattan real-estate market doesn't seem as dizzying as it looks. Second-quarter surveys released by major brokerage firms today show a drop in sales — down 21.8 percent compared to the same period last year, according to Prudential Douglas Elliman — and inventory's up, too. The Brown Harris Stevens' report says the average sales price of an apartment is at an impressive $1.66 million, nearly unchanged from the previous quarter, but that's if you include transactions in those two storied buildings; the figure drops to $1.485 million without. (Everything's still expensive, though.) Another interesting nugget: Appraiser Jonathan Miller, who compiled the Elliman report, says though more apartments are available now than before, at the high end — the top 10 percent of the market, price-wise — inventory actually dropped 31.5 percent. Translation: The rich keep buying, but there aren't enough trophies to go around. —S. Jhoanna Robledo