I don't think so there are apratments for short period in Green park extension area. May be some hotels are there and for cheaper one u can go near Yusuf sarai (But not very gud hotels)and malviya nagar, gautam nagar near AIIMS u can get apratment for short period.

AT IIT-D hostel gate , cars would be there for rent and jaiur is near to delhi and this is rainy season so this time would be gud to go there.