Thanks so much for your require of Tibet tour.
1. If you just only need to travel around Lhasa, Yamdrok Lake, and Namsto Lake, all seasons will be ok. If you need to visit Mount Everest, April to October will be the best time.
2. We could help with your applying the Tibet Permit.
3. We have Tibet Small Group tours , please click the link for detail itineraries: https://www.etripchina.com/tour/tibet/small-group-tour.htm
4. If you want to book the tour, please tell us your travel date.