What are the best accommodation booking options for a friend arriving in Bangkok for a visa process?

If he is landing on 31st he will have to do sandbox and then you will have to apply for his Thai pass and if so he must have a direct flight to Phuket he can not get a domestic flight from Bangkok it must be a sealed vtl flight ✈️

I am finishing up the process myself.

A) Book directly with the hotel. Get a contact and talk to them. They will need to provide a letter saying you have paid for transportation, tests, and accommodation. Originally I booked through agoda and it was a real pain to get the letter.

B) I had to submit my Thaipass twice. Maybe I goofed on the passport number, but when I checked status it said there was no record so I had to do it a second time. Once you've completed the process, check the status so you know they have record of it.

Wait few days, test and go its soon reintroduced, so dont spend unecessary money unless you have to go phket anyhow.

Missing some information.

Is your friend fully vaccinated ?

To be honest you are better off waiting till monday or tuesday to see full details of the new test and go which will be starting Feb 1st. Hotels will then start offering packages to suit.

Which program are they entering on ? Makes all the difference.