Having trouble with the HVAC duct fit

When I was accepted to a good school, I talked to my sister about moving in with her because she lived really close to the school.  She took a while to consider this, but she finally agreed. I had no idea that the two of us would be so different. I am the type that is always cold.  I will be sitting in my room doing my homework, and I will finally be getting warm because I had turned the thermostat up. She comes home and turns down the thermostat, because it is entirely too warm for her.  It had become a real battle. We actually talked about my just moving out and getting my own apartment. She didn’t really like that idea, but we had to do something. I went to the HVAc company and told them about our dilemma and they suggested I bring up the idea of Zone Control  I was willing to take my savings and pay for the cost to have Zone Control put into my room. I assured her that it wouldn’t mean anything would have to be ripped apart. They simple put some bladders into the ductwork so they would be able to separate some air to go into one pipe instead of the other.  She was so interested with the information that she began to look into putting Zone Control into the entire apartment. She thought it would save her money to be able to only heat or cool those rooms that were being used. I just hope she doesn’t think I should pay for Zone Control for the entire house. I’ll refuse to pay anything, if she does.

zone control