The 75-year-old acting icon arrived at the property in Port Talbot with his wife Stella and two bodyguards and asked Chris Trainor and his partner Carly Culver if he could look around.
Hopkins explored the home for 30 minutes and posed for pictures with the couple, who he offered to host if they ever visited Los Angeles, reported Daily Mail online.
"I looked out of the window and caught sight of a chauffeur and he told me he was taking Anthony and his wife to London. Then Sir Anthony Hopkins popped his head out of the car window and said to me, 'How are you?," Trainor said.
"I knew from the previous owner that Sir Anthony had been born in this house and spent a number of years living there, so I asked him in. He had a really good look around the house and said he was born in my daughter's bedroom.
"He said he has got a place in LA and would send us a postcard with his details on it. He said we could visit. At one point his wife revealed that Sir Anthony would be interested in buying this house from me. I made a joke about it at the time, but if they do make an offer, I'll definitely have to consider it," he added.