[speedball1]

I wonder if it's possible that I'm going counter-stream. My understanding is that, in Houston (which is where I am), the sewer drains toward the backyard, but let me give you the layout: The only clean out that I have on this side of the house is roughly under the kitchen sink. Going from that point toward the backyard, you come to the washer drain with the 2" P trap feeding into a T, with the top of the T going to vent and the bottom of the T going to the sewer line. That's about 20' from the clean out. When I snake in from the clean out (toward the backyard), I get hung up at about 10' (about halfway to the washer drain). When I snake in from the vent above the washer drain, I get hung up at about 10' after getting to the T (presumably the snake from the roof is going into the sewer line and toward the backyard, so this theoretically is a different point that is downstream of where it gets hung up when I come in from the clean out--is it possible that the snake from the roof is going in the direction opposite when I come in from the clean out and therefore getting hung up in the same place?). Finally, when I come in from the drain line (i.e. thru the P trap), it gets hung up at the T. Based on this description, let me know if u have any other thoughts.

BTW, where would I get one of those cameras?

As a rule city sewer mains are out in the street. I would check this out. If you're snaking against the flow the snake is liable to come up in a toilet. If you're snaking from a roof vent then you're snaking with the flow. If you snake from the outside towards the house you're snaking against the flow.