In 2018 you can go viral with a bedroom production
Why do you even need me
Why hire a mix engineer if I can go viral with a bedroom production?
Because after you go viral the record label won't be able to get it on radio if the mix is weak or incorrect.
Difference in a producer and engineer
A producer works (usually) for points on the intellectual property and is a part owner of the song itself. They usually work closely with the artist to meet musical and stylistic goals. An engineer, on the other hand, does not own part of the song and is instead brought in as a work for hire to accomplish a task that can be creative or technical.
What do engineers do?
We take the music/project you have poured your time and energy into and make sure that everyone will be able to hear how much time and energy you put into it - weather they hear it on the TV, their phone, or a hi-fi rig.