Kit sets a table with a lamp that does not flatten metallic stamps into a single glare. You sit. The holder may wait in another room. You get time with the gutter, the plate ID, and any scuff the midpoint note already named. If the copy does not match the letter, the viewing ends without theatre.
We use Bangkok most often because that is where copies can be received without inventing a second studio. Chiang Mai and Phuket happen when a collector and a copy are already there. We do not run a travelling fair.
Bring the rarity readout on paper or on a phone. Point at the sentence that matters. “The letter said no restamp” is a better sentence than “I have a bad feeling.” If you need a second pair of eyes, Arun can be on a call; he will not perform excitement for the holder.
Afterward you get a viewing addendum: matched, mismatched, or matched with a newly seen defect. That addendum attaches to the acquisition file so nobody “remembers” the copy as cleaner than it was.