The company recently bought the carriage from Toll NZ. Refurbishment took two months at the company's Cumberland St workshop.
New toilets, carpets, seats and tables were fitted and the carriage was repainted.
A2325 is the first of 12 carriages to be upgraded to replace older models used on tourist excursion services.
Operations manager Grant Craig, of Dunedin, said more than $45,000 was spent revamping A2325.
The company planned to have three refurbished carriages in operation by the end of the year and all 12 in operation in the next five years, he said.
All carriages will meet national rail system standards and operating requirements.
Carriage A2325 will be on display at the main platform at the Dunedin Railway Station between 10am and noon.
