I have a long-haired cat who finds it difficult to keep himself well-groomed. I first visited Stephanie's on the recommendation of my vet (Mason Jones), and have returned ever since. The services they provide are well worth the price!
Most pet groomers do not groom cats -- those that do use anaesthesia to do so. In my opinion anyone can do that (I could bathe my cat too, if he was knocked out while I did it). Stephanie's is a non-sedative grooming facility staffed with wonderful people who honestly care about the animals they groom.
For my cat Jelly, a full service grooming (bath, brush, sanitary and belly clip) runs about $40. For less manageable or larger animals, I'm sure the price varies, but it's worth it to me to ensure that my cat is well-cared for while he's there.
Final bit of advice ~ don't forget to tip your groomer! You tip the person who cuts your own hair, why shouldn't you tip the one who clips your pets' hair, as well?