According to police, Padam Singh, Prem Shankar Sharma, Naveen and Ajay Singh were arrested on Sunday after a trap was laid to nab them.
The gang came under the police scanner following a complaint registered by one of the victims who found that the documents handed over to him were fake.
The gang members posed as DDA officials and lured gullible customers to pay them an initial amount of money for a promised allotment of flat in west Delhi's Paschim Vihar area, said a senior police official.