Portfolio Share %
Q1: Since I only own 50% of my homes I would like it to reflect that as my net worth, not 100%. Is there a way to do that?
Yes.
For every asset, you can set your the Portfolio Share and the asset value will be calculated according to that.
Go to the asset details (click on the 4-line icon on the right side of the row) > Go to the Assorted tab > Find the Portfolio Share field and enter 50% instead of 100%

Q2: I added this asset in my portfolio some time back.
Now when I changed the Portfolio Share, it's not reflecting for the previous dates. I see a dip in asset value. Is there a way to retroactively make ownership 50% such that it isn't included in historical net worth?
Yes.
Click on the Last Update date below the Portfolio Share field > Enter the share as 50% for the previous dates too.
If you want to see how your wealth is distributed across people, trusts, and other entities try Ownership tags. More details