I have a 60 days TR visa(single entry).

an officer in pattaya told me to come 1-2 days before the (60 days) expiration for a 30 days extension + 1900 bahts.(dont forget the 1900 bahts!)

can I ask in same time a multi entry permit?,

my idea is:before my 90 days visa is expired(60+30 days extension), i go to Cambodia, and come back to thailand(same day) for another 60 days.

is that possible or do I have to apply for a new TR(tourist) visa?

what would be the best for me?.

My passport is swiss! I reside in Pattaya.

If you cross the border and come back again you will get 15 days.

If you have a Re Entry Permit it will only keep your original stay alive. It will not add days.

A re-entry permit would only keep your permision to stay alive. IT wouldn't give you any extra days, so you have to get a new tourist visa.

You can get a double entry tourist visa from vientianne and i think you are confused with a double entry visa, which is soemthing else than a multiple re-entry permit.