Going to Barbs's after reading the Yelp reviews helped. In sum, the food can be cheap, filling and a great overall "greasy spoon" diner.
The waitresses were very attentive to coffee refills, but as others have said don't put in a lot of cavies into your order. You are better off ordering straight off the menu with no changes.
I didn't realize it, but they asked if I wanted peppers and onions in my home fries but didn't tell me that was an extra dollar. The coffee is now $1.75, but worth it for bottomless coffee.
My suggestion for future patrons and helpers would be to keep it simple, and order off the menu with no additions. Overall a 4 star diner for its category. Go and try Barbs for yourself.