Is it possible for foreigners to find a one-room apartment in Gangnam?

Hello! It's been 6 months since I came to Korea. I'm currently looking for a studio apartment in Gangnam, but it's really not easy... When I go to real estate agencies, I get rejected right away just because I'm a foreigner ㅠㅠ I've noticed that the expression '는 겸' is often used. For example, a Korean friend said, 'Showing off a new lighter while smoking a cigarette.' I'm not sure what this means. Does anyone know about this grammar? I've tried using the Zigbang app and visited about 5 real estate agencies, but they say it's difficult to get a loan or sign a contract if you show them your foreigner registration card. The deposit is also too expensive... Can anyone recommend a good real estate agency or app? I would really appreciate it if you could share your experiences!