Strettons blamed government leasehold reform plans for the firm achieving a success rate of just 53% at its February auction – its lowest for a decade.
In total, Strettons raised £6.5m, selling just 31 of the 58 lots offered at its 20 February sale at the Grand Connaught Rooms, WC2.
Freehold ground rents were particularly slow to shift, accounting for at least seven of the lots that failed to sell, while small land plots also proved unpopular.
In January, the Law Commission set out a range of proposals that it said would make it cheaper for Britain’s 4m leaseholders to buy their freeholds or extend their leases.
“The market for ground rents is being negatively impacted by the uncertainty around potential future legislation by the government,” said Strettons director and auctioneer Andrew Brown. “The lack of appetite for this type of property affected our overall success rate on the day.
“It is clear that the demand for smaller plots of land without planning permission has also declined.”
Rowfant House, near Crawley, West Sussex (pictured) – in which Winston Churchill spent many hours during the Second World War – was the biggest lot to sell.
The Elizabethan manor house, which is set in 22.5 acres of land and comes complete with a fishing lake, walled garden and streams, sold for £2.2m off a guide price of £2m.
Strettons’ next auction will take place on 7 April at the Grand Connaught Rooms, Great Queen Street, WC2.
