[superuser2]

I'm in the weird position of a freelance audio engineer working mostly on a hobbyist basis. I have 5-6 customers and occasionally 4 or 5 invoices in a month, which means I can't use the free version of anything, but the next step up is designed for a full-time or nearly full-time professional and priced accordingly. I really couldn't justify more than $3 or $4 per month based on my revenue.

The only option for me seems to be Zoho Invoice.