Gustavo Egusquiza knew as soon as he opened the auction catalogue. “I saw them, and I knew I wanted them,” he says of Diane Keaton’s nail clippers. “It was something that she would have used every day, so it was a tiny piece of Diane’s life. It is objects like this that reveal the intimate parts of a person’s real life.”

Egusquiza, a travel journalist and consultant from Bilbao, Spain, admits to being a little celebrity obsessed and is building up a collection of memorabilia that includes Whoopi Goldberg’s teapot and statuette from Larry King’s office.

“There were more attractive things of Diane’s I could have bought. There were fantastic dresses, and hats,” Egusquiza says. “But for me, I didn’t want the typical glamorous red carpet things. I wanted something more intimate, and I think this is the most intimate thing, it will have her fingerprints on it. That’s why I decided to go for it.”

He had been prepared for the nail clippers – which came in a “curated box” with dozens of hair pins and safety pins – to sell for beyond their $200 sale estimate. “Everything was going for far above the auction estimate,” he says. “But I didn’t expect it to get so dear.”

The online auction at Bonhams in New York, earlier this week, quickly passed the $200 estimate, and past the $600 mark. “Then I had a bit of doubt, I really didn’t expect it to get that high,” he says. “But I wanted it, and didn’t mind paying.”

In the end the box – lot 2182 – cost him $960 (£715) including buyer’s premium. He hasn’t been able to look at or touch the clippers yet as he is waiting for them to be shipped from New York to Bilbao.

“At the end of the day, it is an investment in the long run,” he says. “I’ve liked her for a long time. She was so good at her craft, and I think you can see people through the screen and she was just such a likable person.”

His favourite Keaton films are The Godfather and Annie Hall.

Egusquiza, who got in touch with the Guardian following publicity surrounding the sale, won’t be using the nail clippers or pins.

“The box will go on display in my office,” he says. It will join his collection that includes a white ceramic teapot from Goldberg, an Eagle of the Sioux from Larry King, and a signed Chris Levine portrait of Queen Elizabeth II.

Egusquiza says most of his friends and family approve of him spending nearly $1,000 on Keaton’s nail clippers. “They like it,” he says. “I have been collecting since I was a teenager, I don’t think they think I’m crazy. If they consider me eccentric, I remain entirely unbothered.”