I am having trouble with water seepage in my basement, It is coming in under next to my attached garage and an inside footing wall. I am looking at inside drain tile. What should I watch for and what price is expected to pay. One Co. told me I had to put drain tile on my inside wall besides all the outside walls.Is this neseccary. I have 20 yr old outside drain tile.My basement is tore up do to flooding now so I'd like to do something.