Heirs to a rental property

I have an 80 year old mother who owns a 3 family house and a 2 family house next door.  She lives in the main house.  The mortgages are paid off.  The zillow value of the combined properties is about $1.2M.

 

The property is being run by a property management company.

 

I have a brother and a sister who would be co-heirs to the properties when my mother passes away.

 

My question is if we wanted to keep the property as a rental property,  what kind of tax implications are there?

 

Should we create an LLC to keep the property separate from our personal tax situation?

 

Or would it be better to just sell the property and what kind of tax situation might that incur?