Can you suggest a low costing room humidifier that gives me control of the RH?

i need to keep my room around 50%, and i was wondering if there was a humidifer that would let me be able to adjust the relative humidity settings.





please suggest the lowest costing humidifier that could keep me at that RH percentage.Can you suggest a low costing room humidifier that gives me control of the RH?
there are ones sold that you can control the RH, but they are not cheap.

revlon colorstay