Telephone Shoppee with outlets all over Pune (main one near Jnana Prabodhini school, sadashiv peth) can be a good option. He offers a decent price usually

Outlets of Telephone shoppee

1. Main one as mentioned above

2. Off Apte Road

3. Aundh, in the paranjape schemes Riverview. (in the same row as champion sports)

4. Bibvewadi

5. Satara Road, in front of hotel navaratna (close to city pride theater)

6. Kothrud do not know the details

Have not compared with other shops but there is a shop named Nokia Cellcare (I think) on DP Road, just a few shops ahead of the Nokia authorized showroom (which in turn is near the DASS Electronics showroom). All located within a few shops of each other on same side of DP road. They buy old phones or discount new phones based on the condition of old phones.

The price you get for the old phone also depends on its condition. Usually if important functionalities are working ok, you get a decent price. Things like - is the battery ok. Do you have the charger with you etc.

there are a few cellphone shops on Jangli Maharaj Road near Shivsagar Restaurant. They compete with each other and offer a good deal. Gets better if you are planning to buy a new one from them. All of them offer decent repairing services as well.

Digital World in Sagar Arcade on FC Road, near Archies corner on Deccan. You will get the best deal if you buy your new handset here.