City centre apartments are the hardest properties to rent out, according to the Residential Landlords Association, and the young professionals, to whom new city centre developments are largely targeted, are the hardest type of tenants to find.

Professional landlords said that city centre flats were the hardest to let (35%) followed by suburban flats (30%). But houses are the easiest (64%) - with the most attractive being the vintage pre-1940 period (27%) followed by 1940-80 (19%) and more recent post-1980 builds (18%).

The biggest surprise came as landlords nominated the sector where it is most difficult to find satisfactory tenants. The results were evenly split between young professionals and housing benefit claimants – both with 26%. Only 12% said that students were the hardest.

“This result reflects two of the most contentious problems in the private rented sector”, said Lee Dribben, chairman of the Residential Landlords Association. “We have long argued that the fashionable trend in oversupplying city centres with new apartment blocks is not sustainable – and this is now becoming even more evident. Supply is just outstripping demand hand over fist.

“But alongside the young professionals are benefit claimants - and that is because of the government’s new system of paying housing allowance direct to them and the rent is not getting passed on. That makes it a difficult area from which more and more landlords are withdrawing.But to see these two very different types of tenant at the top of the ‘problem’ list, for different reasons, still came as a surprise”, he concluded.