C:\Program Files (x86)\MSBuild\Xamarin\Android\Xamarin.Android.Common.targets(2,2): Error XA0000: Unexpected error - Please file a bug report at http://bugzilla.xamarin.com. Reason: System.UnauthorizedAccessException: Access to the path "C:\Users\IvÃ¡n-2.000" is denied. (XA0000) (BOINAPP)
This smells like a dupe of Bug #14918.
Workaround: Please build your project in a directory that contains only ASCII characters.
*** This bug has been marked as a duplicate of bug 14918 ***