Do you give a "tip" to your contractors or repair people?

[Janice R.]

Hi all,

I've been dealing with contractors or subs so much lately and most of the time, I give a 5-15% tip if the job is done well.  

Recently, an appliance repairman was "hinting" for a tip for a small repair - which I thought was odd.  So what is the contractor/repairman etiquette for tipping?