There are a number of companies in various states that will wash a title for you. I think one I did some years back was in Alabama or Mississippi.

In my case I had purchased a 1962 300SE from an estate in CA that had been in storage during probate for 4-5 years. Of course the attorney managing the estate didn't bother keeping the car's registration current, so when I went to buy it and get the pink slip (a CA thing) the state advised me I would have to pay them the 4-5 years worth of non-op vehicle registration, fees/fines, whatever. It was something to the tune of $2,000.

The attorney gave me a bill of sale, but my state wouldn't accept it, they wanted a title since CA issues titles for all cars.

This was in the early 2000s, and at the time I think I paid $500 to a company that I "sold" the car to, they titled it in their state and then "sold" it back to me.

I got a clean title from AL or MS, wherever they were, and it made my state happy.

Even better, we got to screw CA out of all the money they wanted for non-operational registration, etc.

Understand that in CA, even if you have a car that is off the road and non-operational, you've got to pay annual fees for the privilege.