Accommodations & buses in cities/towns around southern Xinjiang

I will be travelling to Kuqa, Hotan, Kashgar & Tashkorgan in 3rd week May to mid June this year.

1) Accommodations
a) Is it possible to just walk-in rather than book online for all the above cities during the said travelling period?
b) I am a foreigner but speak & write Chinese, will that make it easier?

2) Buses
If I am not wrong, there is a sleeper bus from Kuqa to Hotan.
a) Do you think it is ok for me to buy tickets a day or two before my travel date?
b) What time the bus leave Kuqa & how long is the travelling time?
Thanks