Should I book an organized trip to Leh Ladakh in advance or buy the trip separately upon arriving in Leh?

I will go to Leh Ladakh in July / 2019. I consider these options:

  1. There are many package tours to visit places like Pangong Lake, the Nubra Valley, … for 7 days including accommodation that I can book online now.

  2. Book hotels in advance but buy the short circuit (one or two days) when you arrive in Leh to all tourist attractions via a local agency. Ex: 2-day excursion to Pangong Lake, another 2-day trip to the Nubra Valley. This is possible?

  3. Just book the hotels in advance where I want to go and take a cab to get there. This option is the most expensive I suppose.

Please advise me of the advantages and disadvantages of these options. Thank you