If you are looking for a decent place to stay in South Delhi, then your best bet is this quaint little hotel in Green Park Extension. It's not for nothing that it's got an 8 plus score in Bookings.com.
The standard rooms are small but the cleanliness and efficient services more than makes for the lack of extra space.
The bathrooms are well stocked with toiletries and the bath towels are always fresh and clean
The menu of the complimentary breakfast is fairly limited but still very good, especially the omelette a prepared at a live cooking station
Hotel Southgate is conveniently located in the Green Park neighborhood. The hotel was clean and staff was friendly and helpful. They held my suitcase while I did other travelling in Delhi and that was nice. The room service was good and the laundry/dry cleaning was timely. Will definitely go there again.
In all, a pleasant enough hotel. Its in South Delhi, a distance from New Delhis tourist areas, mitigated by a 15 minute walk to the yellow metro routes Green Park station, giving access to Connaught Place, Old Delhi, and other tourist areas. Good breakfast, including both European and Indian selections. Adequate hot water. Internet is consistent but slow, typical of many Indian hostelries.
Given that we stayed here when there were many events happening in Delhi, the price was very reasonable, and the service really good. As soon as we got in we were shown a room that was musty, but on asking for another, we immediately were given another, and have to nothing to fault with that room. Staff were always willing to oblige, and one of them even used his personal phone to get us a Uber taxi once. There was also a sense of trust. The only thing that could do with some improvement was the wifi connectivity which worked, but kept going off every now and then. Would stay there the next time too, and readily recommend it to anyone.
This hotel is situated in Green Park Extension area very near to the AIIMS, Qutab Minar, IIT, JNU, and only about 20 minute drive from the airport at a non-peak time, but may take an hour if you are in the traffic rush time. The hotel is simple with clean well kept rooms, good service, reasonably fast free wifi, and good breakfast. I think that only a few of their rooms have any windows, and even the ones with a window does not let the window open. So, it can be a bit claustrophobic. But with reasonable prices and helpful staff, this place is good.