Deduction phase-out question.

[Keith Thompson]

Although I owed a duplex as a primary residence in the past, I'm just now getting into multi-families as investment vehicles- mostly buy and hold for cash flow.

My income is moderate, but combined with my wife's we regularly have a gross income over $100k.  I understand that there are deductions that start to phase out with higher incomes, by I'm not sure exactly how this works.  

So what phases out?  

a. Expenses?  I'm assuming that all expenses (management, taxes, water) etc. are deductable.

b. Depreciation- I'm more concerned about this one.  Does depreciation phase out for both capital improvements (shortened schedules) and purchase value (27.5 yr.)  

If so, how would I go about lowering my AGI (MAGI?) to below the phase-outs?

Any resources for a clear and concise discussion of this would definitely be appreciated!