From the southern ridge, Nepal you need to fly to Kathmandu and again fly to Lukla.
For the expedition to Mount Everest, you can either fly to Tibet or Nepal. Choosing your journey from Tibet you need to fly to Lhasa and drive to basecamp which costs additional charges. From the southern ridge, Nepal you need to fly to Kathmandu and again fly to Lukla. So, the flights and jeep added up the cost of your Everest expedition.