When in Rome, throw parties for hip locals. 

That, at least, is what artist Mark Kostabi is doing in his new villa in the Italian city’s Monteverde Vecchio neighborhood, which he compares to being the “Beverly Hills of Rome.”

The prolific California-born artist, best known for once being a gossip column fixture and painting the cover art for the 1991 Guns N’ Roses album “Use Your Illusion,” paid $2.49 million for a three-story property there this spring and immediately set out to turn it into a gathering place for area creatives.

(Kostabi had previously made headlines for doing the same in New York, where he once rented a $14,000-a-month Chelsea townhouse.)

“I’m living the dream in luxury in the one of the most beautiful cities in the world for the price of a one-bedroom apartment in the Big Apple!” said Kostabi, who bought the house with what his rep described as a “deluge of dollars” he received from Manhattan’s Park West and Martin Lawrence galleries, which sold a “s–t load” of his paintings over the last year.

Kostabi found the 5,000-square-foot property, which never formally listed, after reaching out to its broker about another abode — only to learn that one had recently sold. 

The broker then suggested the one he now owns, which Kostabi says he negotiated down, purchased and quickly took to renovating — a process that remains ongoing. 

“I’m currently having a koi pond created in my romantic garden where I want to cultivate million-dollar koi fish and charming turtles,” the seasoned self-promoter told The Post, adding that an appraiser recently informed him his upgrades may have increased the compound’s value to $5 million, “but for me it’s priceless!” 

The home — in which he says he’s been hosting weekly art, music and wine-infused parties for the Eternal City’s artist crowd — had six bedrooms when he acquired it, but he has since knocked down various walls for a better party layout.

As well, he describes, there are four kitchens, five bathrooms, three terraces, two fireplaces, a separate guest house, a wine cellar, a three-car garage and a garden that is “surrounded by famous Italian neighbors.”