You can unlock your mobile yourself at home to unlock your Samsung model mobile using codes are the best way , why i am saying codes means to unlock your mobile with codes are simple & easy way,
Get the unlock code from this site Mobile Unlock Solutions ,it has the best instructions and simple ways to unlock your mobile from the network lock............
If you unlock your phone using the unlock code then your phone gets permanently unlocked....After that, you can use it with any other network's sim card...........