So, how do you deal with the risk of non-payment?
This seems a little glib. Everyone is a risk of non-payment. I have total confidence that over ten years of operation, there will be at least one occurrence of non-payment.
If you're actually providing 0% financing -- you pay the tradesperson $X up front and collect $X over the next 24 months -- that would mean you start out being able to employ zero people, and even the most infinitesimal risk of non-payment immediately puts you in the red.
Pipe is doing a similar thing but their threshold is $100kARR