Minimum number of days a short term home has to be rented?

What is the minimum number of days a short term home has to be rented in order to report income and expenses? And can I report expenses getting the house ready to be rented?

 

In order to get our home ready for short term rental, we had to beforehand do certain improvements to the house for safety and maintenance purposes.  We also had to pay for certain licenses and registration fees to the county/city/state.  We were finally able to get the house ready for short term rental in December '22 and it rented out for 15 days.  The gross income in Dec. was $3,000 but our expenses were $4,000 during the months of Sept to November. 

 

What do I need to report? Income, expenses, neither?