Apartments in Melbourne’s Docklands, CBD and Southbank are being resold up to 24 per cent below their previous off-the-plan purchase price, catching out vendors, many of whom bought them from investment companies or spruikers.

Most are small studio or one-bedders, acquired after the global financial crisis.

Concerns are building about the oversupply situation as a record number of apartments near completion, and banks raise deposit requirements.