CPA with Expertise in Expat Taxes

I am looking for a CPA that has expertise in both UK and U.S. tax situations.

I have tried using a TTL professional however in my experience they can only really provide advice on U.S. tax situations. I would like to go a little deeper and discuss:

- requirements for British citizen's filing in the U.S. if long-term resident and greencard holder
- foreign investment properties

- U.S. investment properties

For reference I am California-based and if possible would either like to video conference with such a professional or meet face-to-face. 

Many thanks for any guidance and recommendations.