My budget so far..

I have used around MYR500 (from 27th Sept - 7th Oct)

Seoul Metro - 35,000
Bus ticket - 18,000
Food - 50,000
Accommodation - 45,000 (3 nights)
Clothes - 15,000
Tour Admission - 4,000

I visited Hye Won on 28th Sept, stayed at Happy Guesthouse for 3 nights until 30th Sept for 45,000 won. Then I stayed with Chi Won (Couch Surfing - free) and now stayed with Joy Farm (practically free but with a yearly fee of WWOOF of 50,000 won).

18,000 won used for ticket from Seoul to Chunyang.

Food is somewhat differs from individual but I try to find Halal food which is more expensive compared to normal food. So, basically it depends on your 'desire' hahaha..

Clothes - I bought a 15,000 won sweater from a warehouse sale in Myeongdong which was cheap. Later, got to splurge to buy a better winter jacket.

Tour admission - Changdeok palace - 3,000 won, Deoksu palace - 1,000 won, Chi Won's mother paid for me a 12,000 admission for Yongin's folk village. She is really a kind mother.

There is a method on how to save on your Seoul Metro expenses but I will tell in another post.