To damage or alter a listed building without consent is illegal and could land you with a criminal record, and a large bill to put things right.

Contrary to what some people imagine, Grade I and II buildings are not all very costly to buy. The recent mystery purchaser of Grade I-listed Castle Goring near Worthing, West Sussex, paid £700,000 for the 18th century pile but the estimated repair bill will be in the millions.

Listed homes are expensive to restore. Experts say that you can add at least 30 per cent to the usual bill as you must follow strict guidelines and use an architect, surveyors, specialist contractors and suitable historical materials.

If you are sold on the idea of becoming the proud owner of a piece of architectural heritage, be aware from the start that you will be regarded as a custodian rather than an owner. You may find it hard to accept that English Heritage might also appear to wish to write your cheques for you.

The buyer of Castle Goring, who prefers to remain anonymous, has already had a few strong words with the conservation officer from English Heritage about who actually owns the place. Some grants are available from English Heritage, the Historic Buildings And Monuments Commission and other authorities for repairs and alterations, particularly for Grade I and Grade II* listed buildings.

Rather surprisingly, most applications for work are approved; English Heritage says up to 90 per cent of listed building consent applications are approved.

Obviously most buyers will expect the listing to add value, which is often the case.

“Listed properties are often character-filled, every room telling a story,” says David Smylie, from Fine Country.