I actually bought a roaming package for my Thai number while I wasstill in Thailand. I'm not sure about getting a sim in Vientiane. Maybe someone else here has experience with that?
I submitted the print out from ABN lookup only. I don't have a business name registered as I trade under my own name. I didn't submit the certificate because it had my old address and I couldn't get it updated in time. The ABN lookup site had the updated address (although it only shows postcode), but it seemed to be enough.
I will cancel when I'm back in Thailand. My school instructed me to see them when I return for the cancellation letter. But I was on an ED extension. I don't know if the same applies on the first three months of the original ED visa.
I showed 6 months 500k balance to be on the safe side. I've read that many people have had success with 3 months balance. Regarding your screenshot, I think you could show them what happens when you take the screenshot and ask if you can take a photo to print instead.
yes, I had internet. I'd read that they sometimes ask to see your banking app and so I bought a roaming data package for this purpose. I'm glad I did. You could print out the screenshot but I suspect they will still ask to look to check that the balance is current.