Except from overnight train, is there any other safety and reliable transportation from Hanoi to Sapa?

(1.) Except from overnight train, is there any other safety and reliable transportation from Hanoi to Sapa, for example express bus? Based on the information that i reviewed, there is an "open tour ticket" for bus, isn't it? and the ticket price is not so expensive if compare with private 4 berth soft sleeper cabin. Where to buy this kind of open tour bus ticket in Hanoi, and how to use it?

(2.) Another question, is the overnight train to Sapa has other cheaper options which can offer a good night sleep too, instead of private 4 berth soft sleeper cabin that is as expensive as USD80 per person?

(3.) What is the best and cheapest way to move around in Sapa, for example to Bac Ha Market, Can Cau Market, Ta Phin village, Cat Cat village, Ta Van Village, Silver Water fall and Ham Rong Moutain? Any bus running between those destinations for travelers?