IRS guidance is as follows:
Vacant rental property.
If you hold property for rental purposes, you may be able to deduct your ordinary and necessary expenses (including depreciation) for managing, conserving, or maintaining the property while the property is vacant. However, you can’t deduct any loss of rental income for the period the property is vacant.
Vacant while listed for sale.
If you sell property you held for rental purposes, you can deduct the ordinary and necessary expenses for managing, conserving, or maintaining the property until it is sold. If the property isn’t held out and available for rent while listed for sale, the expenses aren’t deductible rental expenses.
Continue to claim a deduction for depreciation on property used in your rental activity even if it is temporarily idle (not in use). For example, if you must make repairs after a tenant moves out, you still depreciate the rental property during the time it isn’t available for rent.
See https://www.irs.gov/publications/p527#en_US_2019_publink1000219042 and
https://www.irs.gov/publications/p527#en_US_2019_publink1000219000
