Tax deductions: maintenance/capex/vacancy

[Garvin Yu]

We are meeting with a CPA next month to discuss tax strategies and planning, but we'd rather know a little now than to go there knowing nothing. 

Reading through a lot of posts, we know that mortgage interest, property taxes, insurance, and repairs/maintenance are all tax deductible. 

If we put money aside into a separate account for repairs/maintenance, potential vacancies, and capital expenditures, are these amounts tax deductible? Or does the money have to be spent in order to be tax deductible?

Thanks in advance!