The location is perfect if you want to be far from the hectic center (kadikoy, fatih, taksim). The house is very calm, the surrounding has everything you need: access to the metro station, train station, taxi station, bus station, supermarkets, bakeries, pharmacies, vegetable markets, restaurants and little kebab shops. The flat is half an hour ride from the sabiha gokcen airport which makes it very handy.
The flat has got what you'll need for a month stay. The wifi works really good: I haven't had any interruption with it - I was able to have zoom meetings and stream HD videos often without any bandwidth problems.
The maltepe area has some really nice parks: most notably the maltepe sahil park: never too crowded, a great view on the "princess islands" and a great spot for biking, canoeing on the marmara sea or just for a quiet meditative walk. A ferry also is available to go to the islands.
Finally, I would like to thank Mr Resit for hosting us. He is a very kind host and replies very quickly to any requests. Don't hesitate to write to him if you need anything. The check-in was very smooth. He's helped also get a taxi and talk to the cab driver in turkish after check-out.
I recommend, and I would definitely come back to Mr Resit's place.