Information on depreciation

[Paolo F.]

Good morning,

as I am very small I am trying to fill my tax return for my duplex by myself.

The IRS documentation seems clear but not on houses depreciation.

My doubts are:

1) Should I start using depreciation from the first year even if I do not need it in that year, or I can use it when it is needed? I fear that if I do not use it from the start I will not be able to use it anymore

2) Are there good explanations and examples on how to do it properly?

Thanks for any suggestion