DO NOT do the photocopies of every page in your passport, including unused pages, in B & W. They want them in colour. Photocopies in the Trendy Buildings cost 20 Baht each. Extra 500 Baht for my wife who went for me.
https://www.ajarn.com/blogs/bangkok-...ort-in-bangkok5) Photocopies of your current passport (every page)
Now this is where things start to get expensive. You need to photocopy - in colour - EVERY single page of your existing passport. For me that was a whopping 30 pages at 20 baht a copy. 600 baht! Ouch!