A former ad exec who sold his firm to Microsoft has spent the last 20 years restoring this mansion in Los Angeles -- take a look inside

Leonard fenton artemesiaAnnie ShakLeonard Fenton in his kitchen.

When Leonard Fenton first bought his home — a 13,000-square-foot architectural masterpiece called “Artemesia” — he had no idea just how much work he would end up putting into it. He was in his 20s, and though he had previously restored homes while funding an earlier music career, he had never before worked on a project of this size.

Still, he knew a valuable opportunity when he saw it.

“I’ve always been an autodidact. I always jump into learning what I’m working on,” Fenton said to Business Insider.

At the time of the purchase, Fenton was heading up an advertising firm, Automotive Dealers’ Marketing, that he would later sell to Microsoft.

He called up a few architects who specialised in preservation, consulted the National Trust’s guidelines for historical properties, and got to work on the home, which is considered to be the largest ever built in the Craftsman style.

“The people and sources I consulted often didn’t have the answer, but they taught me how to research and get the right answers,” Fenton said. “I didn’t just want a neoclassical house. I wanted a piece of art.”

Nearly 25 years later (most of which he spent working on the home part-time, though he has been working on the restoration efforts full-time for the last six years), he plans to put the home back up for sale. The home has been on and off the market for several years, but it’s expected to be relisted for just under $10 million.

Let’s take a look inside Artemesia.

The property spans nearly two acres atop the Hollywood Hills region of Los Angeles. Artemesia was originally built in 1913 for Frederick Engstrum, a construction magnate responsible for the Rosslyn Hotel downtown.

Sean Paul Franget

It's situated on a private road and is double-gated, which adds to its secluded feel.

Sean Paul Franget

As you approach, you get a sense of just how big the home is.

Sean Paul Franget

Fenton's goal was to preserve the original intent of the architect, Frank A. Brown.

Sean Paul Franget

But, he says, some of the hardest restoration work happened on the parts of the house you don't see -- the wiring and plumbing, for example. 'This was a very big house on a significant piece of land, but it hadn't had real maintenance done since the '30s,' he said. 'We had to get all of the hard work done, then do the finishes.'

Sean Paul Franget

The exposed wood beams are typical of the Crafstman style.

Sean Paul Franget

As is this porch, which has wide brick support columns.

Sean Paul Franget

Fenton says that now that he has finished work on Artemesia, he wants to expand to help other people restore their homes, and perhaps work on other, larger historic buildings.

Sean Paul Franget

'My approach is really different, and I think it has a place in the market,' he said. 'I want to get in the head of the architect and figure out what their original vision was, but also upgrade the amenities to make it a 20th century luxury home.'

Sean Paul Franget

Artemesia, for example, has a modern kitchen.

Sean Paul Franget

It has plenty of entertaining spaces, too, like this billiards room with its own fireplace.

Sean Paul Franget

This spacious ballroom would be the perfect setting for an upscale dinner party.

Sean Paul Franget

And each of the eight bedrooms has all of the modern comforts of home. Here's a look at the master bedroom.

Sean Paul Franget

The master suite has its own private sitting room.

Sean Paul Franget

But the other bedrooms aren't too shabby, either -- this one's known as the 'second master' and has a beautiful stone fireplace. Artemesia has six fireplaces in total.

Sean Paul Franget

More adventurous types could even sleep on the (rather large) porch if they wanted.

Sean Paul Franget

The property's layout would definitely be appealing to those wanting to spend more time in the great outdoors.

Sean Paul Franget

There are all kinds of fountains, ponds, and waterfalls for the owners to enjoy.

Sean Paul Franget

Wide patios make the most of the house's hilltop perch.

Sean Paul Franget

There's also a carriage house with its own bedroom at the back of the property.

Sean Paul Franget

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