Murtaza bhai kits are safe to buy? i mean genuine S7 will be difficult to find under 30k. Secondly what are your views on verizon and Tmobile phones there are few listed on PG for sale. Also there is an option of S6 Edge+ and note 5. As far the resale is concerned you are right but in case of some phones the whole market refuse to buy (just dekhtay he keh dethay hai Nai ye nai lena) like my last experience with LG. Atleast bikay to sahi loss to yaqeenan hoga
Kits are safe in most cases.
If you have to get one though, get a T-Mobile S7 (G930T).
It's easy to find and works well with local networks.
As for the other phones you mentioned, well Note 5, S6 Edge Plus and flat S7 all have a 3000 mAh battery.
I've owned an S6 edge plus and a flat S7 in the past and am currently using a Note 5 and even though the battery sizes are the same, the S7 still has better battery life.
Note 5 and S6e+ aren't as well optimised as the S7 and hence the battery life is less.
As for your comment about LG phones, well LG phones generally don't sell well over here, at least with Samsung you will make a loss, but they will definitely sell, no one will refuse to buy them off you.
Sent from my SM-N920C