Carl, could we go with Bill's plan on separate entry? Create a new rental asset entry for the guest house, add the new building under that ($250K building value, land value is zero since it's on the same lot as the main house which already has land value added to it from previous years?), placed into service Dec 15 2017. On my FY2018 return I can set the main house rental entry as "converted to personal use" Dec 31 2017 or Jan 1 2018 (just to keep clean cut off date, we did have a few bookings for the main house in December that we couldn't move to the guest house).
Anything I'm missing from above?
Thanks!
