I'd strongly echo this - it's the reason I grabbed some co-founders and started Spreedly. After spending weeks building a billing system for a client and not be

I'd strongly echo this - it's the reason I grabbed some co-founders and started Spreedly. After spending weeks building a billing system for a client and not being at all pleased with the result (bad API, insufficient budget, etc.) I knew there had to be a better way. Billing is the red-headed stepchild of an application, never getting as much time as it needs and simultaneously taking up more time than it should - indicators that point towards outsourcing it ASAP. I think Spreedly's the best option, but even if you don't go with us, please don't do it yourself!