Students are taking out pay day loans to live in luxury flats in a bid to avoid poor standard accommodation, it has been claimed.
Since January plans to build about 3,500 new student rooms in Swansea and Cardiff have been submitted.
The National Union of Students (NUS) said many were struggling to pay high rents in a bid not to live in substandard house shares.
Property advisor David Feeney said the debt was "abstract" to most students.
In 2017-18 alone about 1,700 new student rooms will open in Cardiff, with the majority being studio apartments in high-rise flats in the city centre, including about 450 rooms in the tallest building in Wales, near the John Lewis department store.
A studio apartment in the Fusion development on Newport Road, with a cinema, private dining room and gym, costs £177.50 a week - or about £9,000 a year - while a room in a traditional house share can cost under £50 a week.