We've done that. For years, we rented a snake and did the job ourselves. But, for some reason - every so often - the rented snake would not unclog the line and we wound up still having to call a plumber. We then finally figured out why some times us using the rental snake would not work. One plumber took the time to measure how long it was from our basement stack to the point where our line met up with the sewer main. The run is 140 feet in length. The longest snake we could rent was 100 feet. Any many times the rentals were not even the full 100 feet. Some of the rented snakes had been repaired because of kinks. When the kinks were removed to make the snake usable, the length of the snake got smaller.
So, when we did it ourselves, if the root clog was in the first 100 or so feet, the rental would open the sewer up. But at times, the clog was in the part of the line between 100 and 140 feet. Then even the plumbers had to bring in the extra line to add on to the basic 100 feet to get to the clog. Also, when we were renting the snakes, we had stationwagons or minivans. Our cars now are sedans. The rental snake is a very ungainly thing and would not fit very well in a normal sized trunk. Plus, the older we get, the more difficult it is to use the snake ourselves. Some of the rental were in good shape and worked well, But at other times the rentals were very poor, the switches did not work well and the whole process became too dangerous to do. But the biggest reason we stopped renting was that many times, the 100 foot snake could not reach the clog.
We really have tried just about everything we can think of to try to keep the drains flowing.