Yes, depreciation is on the building only. Land is not depreciated.
When a property is coverted to rental from personal use, your basis for deprecation is the lower of adjusted basis or FMV at the time of conversion. It seems like you took FMV. If that was not the lower of the two, then your depreciation amounts are off.
You compare your original basis (minus deprecation) to the sales amount to determine gain. Since there was a gain, the FMV does not come into play.
