Hanoi to Nanning (and back) Land Border Visa Advice? US citizen

Hello!

I’m planning a trip for August 2026 and could use some help w/ the visa situation for a specific loop I want to do.

The plan is that I...

Fly into Hanoi and hang out in Vietnam for a couple days, and then travel overland (bus or train) to Nanning, China. Explore the area for a couple days, then head back to Hanoi via the land border. Then ultimately I would fly out of Hanoi back to the US. I have a round trip flight from Newark to Hanoi so at this point I will not be changing the flight parts of my trip.

My Questions:

1. I’m a US citizen, and have been reading about all the different types of Chinese visas. For Americans, I know that there are some options of a 10-day transit-free visa, but does that even apply to land borders if I'm returning to the same country (Vietnam)? So in my mind it seems like I definitely need to apply for a standard L-Visa in the US before I leave. Is that correct?

I wanna make sure I can enter via land and also then return to vietnam via land border crossing as well.

1. For a Vietnam visa - Since I’m entering Vietnam, leaving for China, and then coming back, should I just get the 90-day Multiple Entry E-visa? Will the land border guards at wherever I am entering/reentering accept the E-visa for entry? Also which land border crossing would that be?

2. For the Hanoi to Nanning leg, is the international train back in full swing, or is the bus/private van still the better way to go?

3. For the visas, I am assuming that I will need to have my hotels/accommodations listed. So should I book all that stuff before doing the visas?

Any information on this would be of great help, because in due time as the trip approaches I would like to get all my focus on exactly what I need to do. THANKS!