Mechanic needed (Kansas City)

I am in need of a good but inexpensive mechanic to help me with my car.
She started making a noise this past week when this happens the amps go from the norm 14-15 down to 11 then it sounds like it catches and the amps go back to normal.
I have had the alternator replaced about a year ago and when I recently took it to be tested the battery was bad and I have already replaced it.
The alternator tested good.
I believe it is the serpentine belt and or the idler pulley.
I work 2 jobs but I need to be able to get back and forth.
Serious replies only please.
Thank you