Wages for Maintenance People

Hi, I would like to know what the average hourly pay rate is for property maintenance person in Cedar Rapids.

I realize it depends on whether they have HVAC certification, years of experience, how fast they work, etc so if you can include a comment about those issues it would be helpful. I think most landlords would like to know if they are overpaying or underpaying.

Our maintenance man makes $17/hr with no HVAC certification and has worked there for 4 years. He is asking for a raise and I do not know if it is justified.

Any comments would be appreciated. Thank you.