I'm trying to find a movie that came out in the sixties or seventies?

...you just described the basic plot to one of my top five favorite horror films; the plot: an arrogant young newspaper writer stops in a local village pub, where author Edgar Allan Poe is telling chilling stories of horror. The newspaper writer meets the sole owner of a haunted castle called Blackwood, and takes up a wager with the castle's owner, that he can survive a night's stay at the broken down residence. Settling down in the castle, the young writer repeatedly meets up with several mysterious persons, including a hauntingly beautiful woman, whom he falls in love with. Eventually, he finds out that the mysterious persons at the castle are actually the ghosts of unfortunate murder victims, who on this particular night, take solid human form, and are forced to reinact their own bloody deaths. They also need the blood and life force of any hapless visitors at the castle, so that they can arise once more, on the following year. Despite herself being one of the ghosts, the girl that the writer has fallen in love with, tries to save him from the maurading and blood-thirsty spectres...

...the film is "Castle of Blood", from 1964; the director, Antonio Margheriti, remade his film again, in 1971, under the title, "Web of the Spider"...

...the only problem here...I do not recall Vincent Price making any sort of cameo, in either version...

... I hope that this is STILL what you're looking for, though!!!

...check 'em out, below!!!

However, 'Bryce' IS correct, regarding Vincent Price's role in the dull & mediocre film, "House of Long Shadows", and the story DID have something to do with a writer taking a bet, to stay in a haunted mansion....if I recall, I think that the people in the mansion were just strange...but not ghosts...

Could it be House of Long Shadows (1983)?

From looking at Price's career on IMDB, this one seems most likely to me.

I would say it sounds like "The House On Hauned Hill" 1959.