Sensi Lite Smart Thermostat, Programmable, WiFi, Easy DIY, Works With Alexa, ENERGY STAR Certified, ST25W, Most Systems C-Wire Not Required, C-Wire needed with Heat/Cool Only & Heat Pump System -White

Added to original post: ETA: Based on comments, I'll probably return this X2S and try a Sensi Lite (link below). If it works, it'll pay for itself by end of this year. If it doesnt, we'll get a quote from the local HVAC pros and budget for that. As a side note, we've run Honeywell Home RTH6580WF at home and are completely satisfied. The studio has a no-frills "Braeburn" thermostat, and the main unit is in the drop-ceiling which I'd just as soon not mess with DIY. I just never knew "no C-wire" was even a thing. https://www.amazon.com/Thermostat-Programmable-Compatible-Certified-ST25/dp/B0FXN46XRS

Sensi is an Emerson product, does it look like this? https://a.co/d/0ctd5YA2 $65 at Amazon. They run on WiFi so I assume landlord also supplies the internet? Devices are registered to an email, so you can’t add your own account to them. They are “ locked” if you will. You can’t daisy chain thermostats either, you’ll short and blow ac control board fuse. Is the unit ( blower unit) in a closet or an area you can get to? Most importantly. What does your lease say about utilities/AC, etc.