Basis for an primary home and ADU

I bought my property about 10 years ago and recently remodeled by adding to the main house and also an ADU. Plan to rent both the ADU and a part of the addition. How do I calculate basis to depreciate?

 

I have various data points

1. new county assessment

2. my insurance replacement cost assessment

3. the dwelling portion of re-finance appraisal

4. previous county assessment+ cost of construction

 

Out of these which ones should I use as a basis? Since I am renting only a part of the house how do I calculate the basis for that?