Your use of the word "garage" indicates a parking space enclosed by a structure. If that's the case, then that structure has value (as does the land under that structure) and you are required to depreciate it. Now wile I don't disagree with any of the other comments in this thread, I myself would report my ownership of that structure and depreciate it over 27.5 years. Here's what you have to look at in making a determination.
Generally with a condo unit (including the garage) what you actually own is everything from the sheetrock, in and everything on top of the floor joists. You do not own the floor joists or the studs behind the sheet rock. You also don't own the roof. So for example, when the condo building needs a new roof in 10-15 years, the cost of that roof is already included in your monthly condo fees. If not included, (which is not common) then you'll be "assessed" a cost when a new roof gets put on, just as all the other condo owners in your building will be.
If there's a fire the condo association has basic insurance that covers the overall structure. Your insurance covers everything from the sheetrock, in and the floorboards, up to the top of the sheet rock on the ceiling. If the roof leaks, your insurance covers the sheet rock. The condo association's insurance pays to actually fix the leak in the roof and to repair any other water damage that may have occured above the sheet rock on the ceiling.
So in your case for the garage, you actually "own" structural material and if you don't depreciate it, when the IRS questions you on it it's a 50/50 shot weather you'll will or lose the argument. So avoid the argument altogether and deprecate it.
