Is it possible to create a payment term like "50% Net 15 - 50% Net 45"? I tried the installment feature but it still doesn't solve the issue. Or maybe I'm just doing it wrong?

Wouldn't it actually be '50% 15 Net 45'? Installments should be able to handle this I think

Hmmm. Sorry, not sure about the difference. But mine meant 50% is expected to be paid within 15 days from the invoice date and the balance within 45 days from the invoice date.