Samsung Galaxy Core prime 4G in 17000 new without warranty. Phone has no root method so 4G will not work for the next few months.
to be honest, 4G drains battery too quickly and heats up phone more. 4G is way faster than our requirements. So get a 3G phone. Plus, why use 4G when 3G can fulfill your requirements. 3G speed is usually 1-3 mbps, which is sufficient and your budget is low too.
In 14000, you can get galaxy core 2 (3G) brand new with accidental coverage.
Though there maybe other better alternatives by now, lumia 535, huawei etc.
Go for brand new Samsung, huawei or Nokia only.