高価
こうか · kouka · JLPT N3 · na-adj
high price
💎💰 高価 = high (高) + price/value (価), so a high price
高 means high or tall, as in 高い (expensive). 価 means value or price, as in 価格 (price). Put them together and you get a costly item. Sound hook: kouka sounds a bit like coca, and that can be a costly habit.
高 — pictograph of a tall building/tower
高 is a pictograph of a tall structure, likely a watchtower or multi-story gate, with a roof on top, an upper chamber, and a base below. From this concrete image of height it extended to the general meanings 'tall,' 'high,' and figuratively 'lofty' or 'noble.'