Very good price-performance ratio!
We had a great stay at Isidors place. For us, the car parking option was very important. If you travel to paris with your car, you can park it on the ground behind a code secured fence. Also the RER station Gentilly is close by, so we used it every day to get around. Going downtown paris takes you 15-25 mins using the RER.
Check in is absolutely easy, you get a great description of how everything works and which codes you need.
The flat was okay for a city trip. It was clean in general, shower/heating/hotwater was all working fine; towels were provided. WiFi worked really good for my android device and laptop; some others using apple had some trouble.
Walking around in Gentilly was also no problem, we always felt safe while going to the RER or a bistro or a close by market.
Over all we can really recommend Isidors place, it has a great price-performance ratio!