Min Tae Kim went to exchange his hard-earned Australian savings for South Korean money for his return home but ended up in a shallow grave on a vacant property in southwest Brisbane.
Police said late on Thursday that they had exhumed the 28-year-old man's body after blood was found around the grave site in Algester.
Two men and a woman are being held and questioned over Mr Kim's disappearance, although no charges have been laid.
Detective Inspector Rod Kemp said Mr Kim had been working hard at a local abattoir to build up his savings before his planned return to South Korea next month.
But he needed to change $15,000 cash into South Korean won and advertised on the Gumtree website in hope of finding a better exchange rate.
Mr Kim left his Cannon Hill share house with his cash to do a deal with an unknown person about 2pm (AEST) on Monday.
It was the last time he was seen alive and Det Insp Kemp said police were looking into "foul play".
Mr Kim's disappearance comes after 22-year-old South Korean woman Eunji Ban was allegedly bashed to death while walking to work in Brisbane's CBD last month.
The Council of International Students Australia president Thomson Ch'ng said the incidents would rock people's confidence in Brisbane being a safe place to study.
"Two incidents within three weeks is not good for Brisbane and Australia," he told AAP.
"The fact is, international students are important bridges between Australia and the international community and whatever happens here (in Australia), the world is watching."
Det Insp Kemp said it would be very unfortunate if Mr Kim became the second South Korean murdered in Brisbane in less than a month.
"If it is and if he has been brutally murdered, it's a shocking thing for us and a concern for us, most certainly," he said.
