Carbon_Dude is right. Hydraulic lines that comes with the brakes is more than sufficient if you buy hydraulic brakes, i.e., shimano. I think Avid mechanical brakes like BB5s and BB7s come with housing also....not sure but not enough to run full length to the rear. I bought 10 meters of Shimano SP41 housing for the shifter. I run a 1x10 setup. Let's just say that I have enough housing to do another 20 bikes.....way too much but I do have three other bikes to work on so no problem. The shifter cable runs internally for the most part. No housing inside the frame. You will only need a few feet.....a short length for the top and even a smaller one in the bottom.... Lastly, depending on the shifter you buy, it might come with housing already so no need to buy anything additional.
