The latest must-have is not an iPod, a plasma screen TV or garden decking but a modest brick-built garage.

The no-frills structures are becoming such hot properties in Brighton and Hove, they are now nudging into the £20,000 price range.

Several years ago the garages would struggle to fetch £10,000 but in the land and sea-locked city, the prices have almost doubled.

The introduction of residents' Parking permits, the soaring cost of parking generally and the lack of small industrial and storage units for commercial traders has forced garage values up.

Brighton and Hove City Council introduced residents' permits in many central areas of the city.

Motorists have to pay £80 a year to park outside their homes and commercial companies £160.

In some of the most central areas, there are waiting lists for parking permits.

With little hope of the parking problems being resolved and local and central government determined to get motorists out of their cars, garages are expected to become sought-after investments.

Fox & Sons have two garages up for sale at auction at Hove Town Hall on May 26.

One is off Grand Avenue, Hove, and the other is near Lewes Road, Brighton. They could fetch £25,000.

Peter Martin, auction negotiator for Fox & Sons, said: "In the last few years, garages have been fetching very, very good prices.

"This is mostly down to the restrictions the local authority have imposed."

The upward trend began about two years ago.

Fox & Sons sold a garage in Centurion Road, Brighton, for £30,500 because it is near the station.

Mr Martin, who has been in the business for 27 years, said garages were proving to be a good investments for buyers, who can let them out or sell them on.

One of his clients bought two Brighton garages at a London auction and doubled his money in less than a year when he sold them on.

He estimates they could prove even more valuable in the long term.

The most sought-after garages are in the locations where parking is most difficult.

Charles Lewis-Daniel, branch manager of King & Chasemore, Countrywide, has two garages on his books.

An offer of £25,000 was made for one but the sale did not go through.

Mr Lewis-Daniel said: "I think the future of investment may be in parking. People are finding it harder and harder to park. Garage prices are heading upwards. It's something to keep an eye on. It's a bit of an innovative market at the moment."

Farrells estate agents in Hove has a garage on its books priced at £19,950, which is being marketed as two minutes from Hove station.

Parking at the railway station costs a commuter driving to the station each day around £2,500 a year. The buyer would recoup the outlay for the cost of the garage after only eight years.

Gary Vincent, of Farrells, said: "They go fairly quickly when they come up. We also let quite a few."

It is a different story in the other city in Sussex.

Four estate agents in Chichester said they could not recall selling a domestic garage as there was no market in a rural area which did not suffer the same parking problems.

Brighton and Hove's location, trapped between the Downs and the sea has led to land and property reaching premium prices.

In December, two police boxes were sold for a total of £163,000, more than double their reserve prices.

The upward trend for garages is helping Sussex buck the national property trend. Garage and house prices are continuing to rise in Sussex despite an economic slowdown.

Latest figures from the Land Registry show the number of homes sold in the county has fallen by more than a third during the last year while house prices are still going up.