> warning them about the consequences of non-payment and interest on the debt. You cannot simply add in these penalties though, not suggesting you are implying

> warning them about the consequences of non-payment and interest on the debt. You cannot simply add in these penalties though, not suggesting you are implying that. However any such clauses / penalties need to be clearly laid out in the initial contract, and the contract also needs to be legally enforceable. Always check with the relevant jurisdiction what acceptable penalties are, and get a lawyer.