So, Paris... it's an expensive place to stay. Finding reasonably priced location anywhere central is very difficult, so on that basis this is a good option. The location is everything with this apartment. The apartment itself isn't perfect though...
Positives: Location and security (a 2 locked doors to just get in the building). So handy for Metro too (Passy & Trocadero). Very comfy bed (I say bed - it's just a mattress). Free and reliable wi-fi is very handy.
Negatives: The apartment lacks a little TLC - a bit more cleaning and bit more upkeep is needed to keep it nice. The bed is just a mattress and it requires climbing a ladder to get to it - a bit of a pain if you've been walking around Paris all day! And the level where the bed is pretty low - mind your head!
If you're on a budget then this is fine, but if you like a little more luxury then do pay more and bypass this rental more