My parents enjoyed a tour with Korea Travel Mate. This is more for the adventurous traveler (especially young adults), as the tours go to rural areas of Korea and involve simple shared accommodations. Most tours are low priced due to being subsidized by local Korean governments and only for foreigners. Long bus rides and a busy itinerary, but the tour guides spoke fluent English and they had a Kakao group for participants so I didn't worry about my parents getting separated from the group. The drop-off and pick up was in front of iPark mall, so convenient!