if you did not start depreciation the first year they became rentals you should see a tax pro to get this straighten out. you can not just dump the extra depreciation into the current year. you would need to file form 3115 which can be complicated. when you sell you must recapture all depreciation that would have been allowed if you had correctly computed the depreciation from the start. if you don't correct this you will be paying taxes on deductions you never took.
