I am a native of Brittany, but I have lived in Paris for 15 years.
I have a job that makes me travel a lot.
My apartment is situated in the 15th district, you will appreciate "rue du Commerce" 3 minutes walk which ends at a nice market of "Grenelle" on Sundays morning. The market of "Grenelle" is mainly a fruits and vegetables market .
Close by you will find the "Champ de Mars" and the Eiffel Tower.
Near the apartment, another nice Market "rue de la Convention", between the street of "l'abbé Groult" and the street "Alain Chartier". Days: Tuesdays and Thursdays from 7 am till 2:30 pm.
There are many buses that allow you to discover Paris.
The Bus 70 will take you in the heart of Paris at Hotel de ville (City Hall). Next you have "Le Marais" probably the best quarter of Paris, and the museum "George Pompidou", but you can also make one stop at " St Germain des près" or at the Louvre all close by walking, cycling or bussing.
You can also take the bus 80 which will take you across Paris and will stop you at the bottom of "la butte Montmartre" and its "Sacré coeur" church with its stunning panoramic view of Paris.
There are several possibilities to move around Paris from the apartment: subway (lines 12/10/8/6), the bus (lines 70/80/39), Bikes (I strongly encourage you to subscribe to the Velib system).
Paris is comprised of several little villages where walking excursions are very pleasant.
Enjoy your stay. I 'm sure you will.