Having written "ba'Chutz Ta'amod", why does the Torah need to add "ve'ha'Ish asher Atah Nosheh bo ... "?
Bava Metzi'a, 113a #1: In order to Darshen "ba'Chutz Ta'amod ve'ha'Ish"
Sifri: And "ba'Chutz Ta'amod" teches us that he is not permitted to enter the debtor's house even to wait for the debtor to choose a Mashkon and hand it to him. See Torah Temimah, note 117.
Why does the Torah forbid the creditor to enter the debtor's house to take the security?
Gitin 50a: Because the onus lies on the borrower to give whatever security he chooses. Presumably, he will give something inferior 1 - and we therefore extrapolate from here that a creditor collects his debt from Ziburis 2 (inferior quality land). 3
Whereas if the creditor would collect the security, he would presumably choose the best-quality Metalt'lin.
Only the Chachamim decreed that he may claim from Beinonis (middle-quality land) in order 'Not to close the door on debtors' - to whom creditors will refuse to lend if they stand to be repaid with Ziburis. See Torah Temimah, note 121.
See Torah Temimah, nmote 121. Ran (in GItin, Ibid): All Metaltelim are considered Idis (highest quality) since they can be sold anywhere! However here, the debtor is not repaying the loan, but merely giving a security.