Cannot what. Transfer a visa from old passport to new? Enlighten everyone then then. We know you are some sort of farang volunteer :-) PS: Do you get a uniform?
Are they cheaper here than elsewhere? I have no idea but it seems a lot of effort for little return given costs of travel etc. For many other products you see Thais flying to Singapore. I remember the Thai girls at a company I worked at would buy bags etc on business trips as much cheaper ie going to Belgium they woukd do a day trip to Paris for LV etc. We used to laugh about it.
What items are cheaper in Thailand to take advantage of this? Watches cheaper in Singapore or Switzerland. Thai fly there for the high end. Electronics not cheap in Thailand. VAT is only 7%. Not much room for arbitrage?