DIY piano climate control?

I’m moving my upright piano into a recently converted garage space. The door frequently gets left open in the summer but i’m trying to get better at that.

There is an A.C. window unit and a small gas space heater. I really don’t want to invest in a $700 Dampp-Chaser (maybe when i finally get my Yamaha C7), so is there some compelling reason I couldn’t just place a couple of hygrometers inside and regulate the RH with THIS and THIS

I’m in central TX, btw. Mild winters, hot summers. Average yearly RH is 82% am and 59% pm

Thanks yall