Property ownership - if I still have a mortgage left on rental property, am I considered only owner of property? Do I own 100% or less than 100%?

[MichaelL1]

The mortgage does not determine for tax purposes your ownership.  If you are listed on the property tax rolls as owner, you own the property.  

You are the owner, the mortgage company just has a lien on the property until the mortgage is paid. 

Once the mortgage is paid off (great day when that happens) then you own the property free and clear.