I had a kitchen sink drain back up that I could not get with my manual snake. Cost me $200.
RotoRooter wants $70 to clean a drain, but they came to my house and the guy was an idiot and his power auger didn't work so I elected to not use them.
ARS is probably the most expensive plumber in town, well maybe not as expensive as village plumbing. Their benefit is that they will likely show up on time and you will get a service guy who is not a felon.