1. What does it mean?
쿨거 shortens 쿨거래, cool transaction. Sellers commonly use it for a buyer who agrees promptly and does not prolong the deal with repeated negotiation or unnecessary back-and-forth.
Also written or said as 쿨거래, kulgeo
2. The nuance
It does not mean you should skip essential questions or payment protections. '쿨거 시 할인' is an offer with conditions, not a universal rule.
3. Examples
“가격과 상태를 확인한 뒤 바로 결정해서 쿨거했어.”
After checking the price and condition, I decided promptly and kept the deal straightforward.
“쿨거라도 구성품 확인은 하고 거래했어.”
Even for a quick deal, I checked which accessories were included.
Sources
References support the meaning and usage. Example sentences are written for NoCapWiki.