The orginal question was Question ID: 438974 with the subject above. 
I have reposted it after this follow-up question.

A loan was made and community funds used for payments.  Using the
forumula value/principal-payments applied, upon what date is the real
property valued?  Date of death or execution of the loan? Or? Lets say
25,000 loan was funded in 1980 and paid off in 5 years.  Considering 1980
vs. 2006 there is a very large difference in values and consequence.
Or is this even the correct formula to use?  MUST a recorded trust
deed and note be in the chain of title?  Is it sufficient that a joint
account was used to make payments regardles of the amount of
contribution by the surviving spouse to that account(s)?
Please provide references. 

Orginal question:
The scenario:  The husband dies without a will (intestate?).  His home
(his only real estate) was acquired prior to his current marriage. 
The estate and the deceased are in California.
Is the real estate still his sole and separate property?
What, if any, portion of the estate are his daughters entitled to?
How would contributions to the real estate made by comingled funds be calculated?
Please provide references to law or case law.