...trusts? Trusts, revocable or irrevocable are expensive! Is there a general rule of net worth/financial assets before one even considers doing this?

Example, I have the following assets in NC and no where else:

House - joint tenancy
2 cars - both in my name
Bank accounts - Joint
Life insurance - we are owners of our own policy with each being beneficiary of the other's policy.
Company 401k - again, we are beneficiary of the other.

And three beautiful children:

Do we need to re-title to the trust and which one, revocable or irrevocable. What is the advantage of one over the other besides the ability to change and can't change?

Also on the house, since I am no longer owner does that mean the trust gets the 1098 and I cannot claim mortgage interest on my return??