Hey there! It is better to choose a tour operator and go in a shared/private cab. Do not go on booking a different car everyday as it will make your trip tiring. Find an operator and be sure to not fall into the traps of cheaters if you are going via Siliguri / New Jalpaiguri. They'll try to lure you with many unconditionally cheap offers but they will later on loot you in every other trip they provide. Never book a hotel from the tour guides. Do your own booking and go. Tsomgo Lake+Baba Mandir+Nathula Pass have a single day package of ₹1200 Per Person. Gurudongmar Lake+Yumthang Valley (which is a 3 day tour) has charges of around ₹3000-₹3500 Per Person. Rates are applicable for a shared jeep. If you wish to go to Zero point or Kala Paathar, you need to talk about that with the driver. He might take you there at a charge of about ₹300 per person for both. Hope you enjoy!