Usually they will not give you the full value. Depending on how "safe" they deem the security, they might only allow you to borrow 50%-70% against it. And mos

Usually they will not give you the full value. Depending on how "safe" they deem the security, they might only allow you to borrow 50%-70% against it. And most (probably all) of these forbid you from using the loan proceeds to buy more securities.