We spent 15 days in Tamara's apartment and I could say that overall our experience was good. Tamara was very helpful and nice to us and also very fast at replying to emails.
The most important asset of the apartment is that it is in a very convenient location. It is 2-3 minutes walking distance from the 'Nation' metro station, close to supermarkets, a pharmacy and many convenience stores.The area seemed also very safe and both me and my sister felt safe walking from the metro to the apartment on our own late at night.
The size of the apartment is perfect for two people. The bed was very comfortable and we had almost all the comforts we needed: hot water in the shower, fast internet and a few basic kitchen utensils to cook.
Nevertheless, we were a bit disappointed that we were only informed after our arrival at the apartment that the washing machine does not work and hasn't worked for a while and that we needed to take our clothes to the launderette. That's not a tragedy of course but I wish we had been informed about it before booking because the washing machine was one of our criteria when we were trying to decide which apartment to book.
There was also a small issue with the window which could not be properly closed and sometimes opened on its own when it got too windy. This was however tolerable given that it was August and the weather was still good!
Overall I'd say that Tamara's apartment is a good solution if you need a room to stay for a few days in Paris and you are on a tight budget!