brand new options: Honest openion is Huawei honor 8 lite 5.2 inch and 3k mah with usb otg support, good sensors and good performance of cpu even can play high end games , y7prime all above features with 5.5 screen and 4k mah battery. Both will cost around 21k.
Then both these slight used will b at 18k.
Then in used the good phones are in other brands are Motorola, samsung, sony, huwawei.
If you fan of apple the 5s can b available but used.
If I was in your position I will go for y7prime simply big battery fast charge and big screen . I watch alot of youtube stuff on mobile.