Electric plans Question

I'm moving to Houston soon and will be living in a 1 bedroom, 1 bathroom apartment that's around 800 square feet. So I'm currently researching electricity plans. I've read that it's best to avoid the tiered plans, which charge different rates per kWh at various usage levels like 500, 1000, and 2000 kWh. The recommendation I've seen is to get a flat rate plan where you pay the same rate no matter how much electricity you use. However, every provider I check on Powertochoose seems to offer only tiered plans. Does anyone have suggestions on how I can find flat-rate electricity plans in Houston? Also, since I'm not sure what my electricity usage will be in the new place, would it make sense to start with a short-term, flat-rate plan for the first few months and then shop around during December or january when rates are lower? Any advice is appreciated!