Frank is a general partner and owns 70% of partnership XYZ LP. The other 30% is owned by limited partners. The partnership was formed on January 1, 2021. On January 1, Frank contributed $24,000 cash, and a building with a basis of $400,000 and a FMV of $550,000. XYZ had taxable income of $60,000 for year ending December 31, 2021. At December 31, 2021 XYZ had liabilities of $150,000.

What is Frank's outside basis in the partnership on December 31, 2021?