Everything is expensive in Nepal these days. I went to Nepal last year after many years for Dashin, and realized how badly inflation has hit the country. Food prices, prices of clothes, rent has all sky-rocketed. 
I wondered how poor people in Kathmandu are surviving amidst all these. 
So it's not just the land prices that has gone up. 
I would, personally, blame the very corrupt political situation for all that's wrong with Nepal.