A chapter by chapter verse by verse study of the book of Proverbs.
Exodus 22:26-27 says an Israelite could take someone’s outer garment as a deposit or a guarantee for a loan as long as they returned it each evening, so it could be used as a night covering or blanket. Solomon’s advice here is that if you loan to someone who has already foolishly agreed to be surety for a stranger, make sure you get the deposit or guarantee. If they were foolish enough to be surety for a stranger, they should be regarded as a credit risk. 
There are some people who will do foolish things to fulfill their lusts.  We have looked at several scriptures in Proverbs that have talked about the man who deals with strange women, or prostitutes, or harlots, he is foolish. Other Proverbs have taught us about the one that's surety, or a co-signer.  It calls these people fools in the Proverbs.  And it says these are people, if you're going to loan something to or do something with, take collateral from them or you are going to pay for it.  If you are going to loan one of these guys money for what ever reason, get collateral. This is not a good investment. This reminds me of Tamar, she was wise in securing Judah's seal, cord, and staff as collateral, so that she could
hold him responsible for what he had done to her later. Genesis 38.