How to find a goshiwon near my university?

I'm looking for a goshiwon (small studio room) near Konkuk University. My budget is quite tight - ideally under 350,000 KRW per month including utilities.

I've been searching on Naver and Zigbang but most listings are in Korean and I can't really tell which ones are good. Are there any websites or apps that are more foreigner-friendly?

Also, what should I look out for when visiting a goshiwon? I've heard some of them can be really tiny and have shared bathrooms. What's a reasonable room size to expect at this price range?