Sale of rental property gifted to me

In early 2022 a family member passed away and their home was rented out.  The home remained in probate until mid-2023, at which point it was gifted to me from the new official family member owner.  I owned the property for a few months then sold it in 2023. 

Questions:  what value do I use as the cost basis (date of death in 2022)?  Is it ok to use comps via Zillow or other records to establish FMV from 2022 since appraisal was not done?   How do I calculate cost basis for the property gain/loss purpose?  How do I calculate Sales Proceeds amount I sold it for gain/loss purposes (sales price, closing costs, etc)?