You simply cannot take possession of just your half of the collateral, and you therefore do not have a complete interest protecting the bank from loss. Without a complete interest, the loan is unsecured and the lending policy may be violated.
Seek a hypothecation from the other owner. They can pledge their interest without having an obligation on the debt. If they don't agree with this, you'd never get that collateral back in the first place.
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AndyZ CRCM
My opinions are not necessarily my employers.
R+R-R=R+R
Rules and Regs minus Relationships equals Resentment and Rebellion. John Maxwell