You have to be a romantic and have a love for history and old buildings if you want to buy a castle.

Elisabeth von Elmenau grew up when Sissi, the 1955 film starring Romy Schneider as Princess Elisabeth, was a big hit. Back then, she imagined living the life of the princess in the castle Possenhofen in Bavaria.

Fittingly, von Elmenau, who was also nicknamed Sissi, began to harbour dreams of living in her own castle — minus the crown.

After a 15-year search for the right property and two years of renovation, that dream came true in June when von Elmenau moved into her castle Bullachberg in Bavaria which boasts views of King Ludwig’s famous Neuschwanstein castle. The property, built in 1905 in the turn-of-the-century style, comprises three buildings and barns totalling roughly 2,000 square metres (21,527 square feet, with 900 square metres (9,687 square feet) of living space within the castle itself.

"You have to be a romantic and have a love for history and old buildings if you want to buy a castle," said von Elmenau, now 59. "I saw many castles in Austria, South Tyrol, Switzerland and Germany. Then I found my castle by chance from friends in the area."

But, if you’ve got the time, money (expect to pay hundreds of thousands with renovations) and patience, you can buy a castle. Here’s how.

How to find a castle?

Christoph von Schenck, the head of Castles & Manor Houses at Engel & Völkers in Hamburg, said you'll need a specialty agent to find a castle, since their sale requires knowledge of local law and regulations, particularly around preservation of historic properties. In addition, many sellers of castles demand discretion and won't hang a "for sale" sign.

What’s more, when castle owners hit financial trouble, they’re likely to sell off land around the residence, before they sell the castle. That can mean many buildings for sale lack land—as von Elmenau discovered.

Dozens of websites feature castles for sale in Ireland, France and Germany. If you don't recognize the agency or company name, find out which professional organisations the agent belongs to before investing too much time. Besides Engel & Völkers, other agencies with historic residences include Sotheby's, which has regional affiliates, and Christie's International Real Estate.

As with any property, buyers face the problem of beautiful photos versus not-so-beautiful reality, said Bernd Neuhäuser a founder and the head of Vermittlung historischer Immobilien OHG, an agency in Germany. A reliable agent can help a buyer weed out properties that aren't fitting.

In Germany the market for historic buildings is "stable"," said von Schenck, and one reason for that, according to Neuhäuser, is the number of properties in the eastern part of the country that are back on the market after being snapped up post-reunification.

"Some buyers underestimated the costs of restoration and got only partway through the job. Now they're trying to sell," Neuhäuser said.

Stable prices in Germany compare to France, which has seen prices sink since French president Hollande introduced a 75% tax on the extremely rich in 2013 and the market flooded with historic properties. 

How much does it cost?

Not all castles are priced for the rich and famous. A castle in Germany can cost the same as a holiday home in Spain, said von Schenck. "It just depends on your lifestyle and what you want. Castles in Germany are now affordable for the middle class," he said.

Engel & Völkers usually sells six to 10 castles in Germany per year from its catalogue of 60, and it estimates that up to 100 are for sale across the country.

For 2014, sales might rise, he said. "We've had strong interest from the Chinese. "The lowest price for an historic home listed by the agency in late June was 338,000 euro ($459,555) for a house in Belgium; the highest was 15m euro ($20.39m) for a Venetian villa from the 1600s on the Brenta river.

How to renovate it

For starters, have a good architect who knows the ropes for castles and historic homes and can do a thorough check on the substance of the building. Be prepared for surprises during renovations. And expect to pay premium prices for the right craftsmen, materials and the proper insurance. von Elmenau said building new might cost 2,500 to 3,000 euro per square metre but restoring can cost  4,000 to 5,000 euro. With each requirement to preserve the original look and feel, prices can rise. Owners may need to have tiles custom made or stucco rebuilt by hand by an artisan who is specially trained in that area.

According to Schenk, financing through German banks is possible also for non-Germans.

Bring a good dose of patience. Authorities from historic preservation offices, in Germany the so-called Denkmal Amt, will have an opinion on most renovations you make, in some cases even those inside the property and not just on the facade.  In addition, private organizations may try to block plans that they feel may "threaten" the artistic heritage of a property.

"I wasn't allowed to install new windows,” said von Elmenau of her two-year renovation, declining to say how much she paid to buy and restore the property. “I had to restore the existing ones. I couldn't buy new doors either. Thank goodness, I didn't need a new roof. It's far more expensive to restore a building than to build new."

Check for tax breaks granted for renovation. In Germany, tax write-offs can be worth 90% to 100% of the amount invested in the property over 12 years.

What expenses to expect?

Von Elmenau expects her maintenance, gardening, heating and personnel at castle Bullachberg to cost about 5,000 to 8,000 euro ($6,798 to $10,877) per month. She hopes to cover most of those costs with income from events she plans to hold at the property.

"Many people find out they cannot afford to keep a castle after buying one." Castles have always been something for people with money and lots of love, Neuhäuser said.

For von Elmenau, love is indeed part of her business model.

She has signed an agreement with the local government so that weddings can be officiated at her castle, with a full view of Neuschwanstein. In September, the first wedding party arrives from the US.

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