I tip the Barber every visit.  Bring a jar of nuts.  If you don't tip, then figure what you spend during the year and add10-15%.  Lunch guys, well they are salaried guys but perhaps the Jar of nuts also.  
I suppose you can also figure what you spend and give them %.  They are not "servers" so its not like tipping a wait staff.  Maybe 5%?  
Im suprised OBM (Orange blobman) didn't say " I don't tip, they tip me"!