Buying owner-occupied home with ADU: MCC, depreciation, and taxes

[Eric Pruett]

I'm submitting an offer on a home for our family. The home has an efficiency ADU (converted detached garage) which we will rent out.

The property is also in a targeted area, so I qualify under increased income and purchase price limits for a mortgage credit certificate, which would save me ~$1600 per year.

I’m a complete newbie on real estate (schedule E) taxes, I just know that I can take depreciation based on bedrooms or square footage.

Questions: 

• Does an efficiency count as zero or one bedroom? (If zero, I assume I would have to use square footage method of proportionality for deductions)
• Am I still eligible for MCC as an owner occupier if I rent out a portion of the property? (I believe so)
• How does MCC work with a split use of the property? I know when deducting interest expenses on schedule A and schedule E you split it proportionally based on square footage or bedrooms. Am I only eligible for a proportional amount of the MCC which is not rented out or does filing a schedule E invalidate me from the MCC program? What tax form do I need to look at to verify this?
• How does this work with depreciation? If MCC is incompatible with interest deduction and depreciation, how should I compute whether it’s better to use a MCC or to forego it and take depreciation?