Hi Zout
Wages for hired painters vary greatly, not only from state to state but even from city to city...Though most union painters (with a journeyman's certificate) can make $20/hour or more in larger urban areas, non-union painters in smaller markets are usally lucky to make $10...In Fargo ND, for instance, a journeyman painter (at least three years experience) usually makes no more than $12/hr (with or without benefits), and a foreman or leadman rarely gets more than $15. A three hour drive down I-94 will about double that wage in Minneapolis...
It's going to depend on where you are and whether you're in a "right to work" state...I think there are also wage calculating sites you can go to to see what the prevailing wage is in your town, but they aren't all that accurate...
Luck