How can I better control my home energy cost?

Keeping your filter clean. Energy saving programmable thermostat.

How much maintenance does my hvac unit need?

Twice a year once in spring and once in fall.

What causes AC units to freeze up?

Dirty filter

If I replace my outdoor unit, do I need to also replace my indoor unit?

No but a matching unit can boost efficiency of AC. However when you replace outdoor unit the indoor coil will have to be replaced.

Why Do I Have Poor Airflow?

Dirty filters are main causes of poor airflow.