All these tours are included. You don't "book" them. Ben Thanh market is last place to buy things. I didn't plan on "shopping" a lot, but things are so cheap, you just do. Names on all streets in Saigon have been changed by communists.
I love this sort of thing and its frantic atmosphere but with less than an hour here it was a little to frantic for my taste and I hardly got to look at the various stalls much less buy anything.This is really a full day excursion and not for the faint hearted
Just walk there yourself, no need for a guide. It's hot, crowded, noisy, irritating sales people, stuff, stuff, and more stuff. You just have to experience it, keep looking - there will be something you want! Bargain your head off, then walk away and they will chase you to get your last offer. We have been three times, got great buys each time.