Fuel filter is probably situated below rear seat so, take your rear seat out. There are two spring releases that you push in and pull the seat cushion upward. Under the seat cushion you will find a fuel sending unit cover that has a rubber or silicone seal around it. Carefully take this cover off and you will see the sending unit in its entirity and you will see where the fuel filter is to the right. Most people will be discouraged to try to replace the filter themselves because it is almost hidden...There are two ways of doing this. One -- if have enough balls and knowledge you can lower the gas tank to get at the fuel filter better. Make sure you know what you are doing or you could mess up your car and maybe cause an explosion....The second way is just to cut (rotary tool or other cutting tool) around the fuel filter so it is in clear view. Just be careful not to cut any fuel components and do not use a torch......regarding fuel consumption...it depands upon how u maintain ur car and no. of time u send ur car to service station for service......
Good luck.
Good luck.