What tax deductions on rental income are added back to DTI?

[Jose Pad]

I was recently denied refinancing my duplex because I claim too many expenses on my rental income such as repairs, taxes, etc... I was told good lenders add back depreciation. What else can I deduct that won't hurt dti for future loans? This year I only deducted depreciation from my rental income as I was scared this might happen again. Thanks!