I recently switched my invoicing system from Simply Invoices to Fresh Books. Simply Invoices was great while I used it, but the complete lack of customer service forced me to switch. Admittedly, I was using their services for free, but I repeatedly requested/suggested new features that would not only benefit me, but all users, with no feedback whatsoever. Maybe this was because I was not a paying customer, but I doubt that even if I was paying for the service, I would have received any feedback. I switched to Fresh Books because they had the features I was looking for. Upon switching, I received a phone call and an email from their customer service making sure that I was satisfied with their services thus far.
If you expect people to pay for your services online, you need to engage your customers. People want to know that there is someone behind the curtain. I don’t mean to single out Simple Invoices, they provided a good service to me for free. The problem is that there is plenty of competition on the web. I can easily go elsewhere if I am not satisfied with your service. In this case, I switched to Fresh Books. They not only had the features I was looking for, but followed up with human contact.