I'd go around and see the guy face to face, offering your help in arranging more payment terms to suit. Quite often people are very ashamed when they get into financial trouble, and try to avoid the problem completely.
When I first met my husband he had this attitude. It took me a good solid week of ringing around the debtors and negotiating new payment terms, but they were all very appreciative to be told what was going on, and very receptive to negotiation. This was finance companies etc, mind.
The annoying thing about my soon to be ex husband is that he had the money, he was just really bad at prioritising and paying bills! Maybe your mate is the same.
I reckon you might get more joy out of talking to him, than as you say, $5 a week through small clams. (The I is missed out deliberately, cos that's all you'll get.)
Illuc ivi, illud feci.
Buggrim, Buggrit.
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