Basically if you work through the property (and any other assets listed there) in the assets/depreciation section, you'll have a box for business use percentage. That will be 100% business use. The only way it would be less than 100%, would be if you used the property for personal use *while it was classified as a rental*. While not unheard of, it's somewhat rare.
Also, your number of days rented day count starts from the day a renter "could" have moved in, which is usually the day you put that FOR RENT sign in the front yard. The day count also includes vacant periods between renters, provided you did not use the property for personal use for one single day while it was vacant between renters.
