Are you in Orange County, CA. Some of these answers are coming from out of state and the laws are different.
Usually the bank will not let you be on title unless you are on the mortgage.
Have you fiance talk to the escrow officer and tell them what he wants. It can be set up to be done as soon as escrow finishes, all on the same day.

Wow. Vested title regardless of the father and commuity none the less.

And you walk scott free as you are not a debtor to the note (only providing an endorsement to ensure the lenders ability to recover) Outstanding. admin@borrowerhotline.com

GREAT QUESTION: If all is correct YOUR name is on deed, he cant ever sale the property unless you agree to terms I would get all in writing what you rights are and % of income earned off property if sold. Tax benefits, and etc.

Leaving you off the mortgage is a common practice these days. Having you on brings nothing to the party, but your debt and that would skew the debt-to-income ratios that are so important.

Having his father on the deed makes sense in that, how can he make sure that the maintenance is being done and protect his part of paying back the mortgage if he doesn't have an interest in the property? The mortgage company would insist on it.

As far as precautions and entitlements:
When you talk to your attorney during the purchase process, have them go over the different types of tenancy in regards to the new deed on the property and everyone's rights.

I would also put the particulars of everyone's role in the transaction and down the road on paper with your attorney. It should be something simple and should draw the line between his father's role, your role and your fiance's role. Use the attorney to do this part as well so that you can be sure that the agreement is in line with everyone's duties under the mortgage and your rights under the deed.

A little prevention now can save a lot of legal fees later trying to determine how things happen as you progress to refinancing the house to get his father off the mortgage and what that means to his name on the deed. You will also be ready for the maintenance of the deed down the road as you get married or worse case scenerio, you end up leaving and need to have your name removed from the deed.

I hope that helps.