Totally agree, I was told about 25 years ago when I first came to Hua Hin to Rent a property and buy a car, and I have always stuck to that, just look at the amount of resale property on the market, and how long it stays there !
It depends which agent at which immigration office, there's no conformity here. I did it this year with my wife as well, in other words she is included with our translated and certified marriage certificate.