$67 for a lube and clean? Even for four engines, might take an hour at most. I'm in the wrong business. Now if repairs need to be made, that might cost more.
There's a guy I know that repairs trains. He has a bench fee of $15, I think. Then he has charges for certain things. Clean and lube is $10. Repair work is $8.50/hr plus parts. He's not gettin' rich, but it keeps him out of trouble and in good standing with SWMBO. (She Who Must Be Obeyed)
He repaired a couple of my engines, and it cost me having to weather three SD40's for him.
Bob