Hahaha street food really that expensive in Korea huh? Then I will mix street food with some nice restaurant treats.
Thanks for the suggestion, then I think I will add two more days to my original plan, go for 10D9N instead of 8D7N. Didn't expect Jeju Island is so big

Just got Air Asia flight tickets to Korea in October, will be spending 11 days there.
Would like to ask about whether this plan is OK:
Day 1 reach Seoul around 3pm. Stay for one night.
Day 2 morning straight fly to Jeju from Gimpo, stay for 3 nights.
Day 5 morning fly back to Seoul. Day 5 to Day 11 spend in Seoul.
Because I worry if stay in Seoul first, when need to go to Jeju, need to carry heavy luggage (extra items from shopping trip in Seoul). While in Jeju I think won't shop much kot.
Is the above plan reasonable?
Haha yup good suggestion, I think the first day when I reach Seoul I will just go straight to Jeju. Plan to spend 4 days in Jeju before flying back to Seoul.
6 ~ 7 days in Seoul I think still OK, actually I was thinking of spending few days in Busan too, but too bad already bought the flight ticket back, which is from Incheon to KLIA.
First time visiting Korea, didn't know Busan also have flights back to M'sia.
And the train fee from Seoul to Busan is so expensive
If I visit Korea again next time, I think I will focus on Busan area.
jeju is big and some attractions from another is quite a distance. driving speed there got limit so can't speed so it takes longer time to reach haha.. it's a place to chill and relax though. i suggest to rent a car there..
the plan is ok. you can either stay few days in seoul before depart to jeju. you can store your luggage in the guesthouse or hotel and bring a small bag over to jeju. condition is that when you return back to seoul you have to stay back at the same place.. go to KTO msia take the booklet. they have some useful voucher for you to use. actually the train fee is reasonable price ler..