It is less complex, in my experience. No visiting or photos. Map is simple drawing of home location that takes two minutes. I have never used an agent, but if it seems too complex, please use one.
An easy way is to take your blue book to a shop where they do annual car inspections. For a fee of one hundred baht they do everything and you come back in one or two days to collect your sticker.
Although it is called a survey, I did get an appointment by registering on it. Please persist. I have received two Pfizers from them in spite of not being a patient there. Good luck again.
They now accept over 40 at Bangkok Hospital Pattaya. Register by 27/8.
https://docs.google.com/forms/d/e/1FAIpQLScaN6-qHrki6-EeOEfaHtyh5l1o20VzGiTYsCRIWlTFqQ6NWw/viewform