As I said, all DLT offices operate differently. They are supposed to be 'One stop shop's'. In reality they rarely are. Take a foreigners yellow housebook. That is supposed to replace needing a residents certificate. For the last few months, they are not recognised anymore in Chonburi province for driver licences and vehicle registering. They will hand everything back to you and send you to immigration to get a residence certificate.
Ray, a straight forward transfer of a car already registered in your province is ok. It can become an issue when purchasing in one province, then registering it in another province. You may actually need 2 residency certificates depending on each DLT. It also depends exactly what your local DLT actually deals with. Pattaya DLT, which is huge, only deals with licencing and testing etc. Car registration and inspections have to be done at Chonburi DLT itself.
He will need to sign a power of enterny form if he can't do it himself. There are agents that can help once you have all the paperwork but I don't know of one personally.
I'm really not sure how you get around it now. It's a double problem as it's registered in another province and needs an inspection at the DLT and a plate change.
Garrett Greenwald basically you've paid for a vehicle that you don't own. You never, ever conclude a transaction here until the title has been changed.
The real big headache comes when you buy a vehicle in one province and attempt to register it in another province. You then have double paperwork and inspections to deal with.