Stayed in the Hotel Duo as a solo traveller in Paris for 4 days.
Really nice hotel, lobby is really trendy with an art deco.
My room was a single room and it was just what you need for a solo traveller.
Comfy bed, plenty of luggage space all the facilities you need, if I was going to be really picky I would say bathroom could be slightly bigger but it wasn’t a problem for me.
Location of the hotel is ideally central. You can walk to Notredam and the Louvre within 15 mins from the hotel, there is also a metro stop right outside which is on one of the main metro lines.
There are plenty of nice restaurants, bars and jazz clubs near by.
The staff are very friendly and knowledgeable
Now I have found this gem in Paris I would stay here again