We live in a Community Property state (TX).
When we each itemize deductions are we to split the property tax (max 10K) so $5K ea? We paid the PPTax from a joint account.
Yes, your filing cap is $5,000 for the State and Local Tax (SALT) deduction if you are using the Married Filing Separately filing status. For more information, review the TurboTax article Which deduction should I choose, state and local income tax or sales tax?