I agree that a potential client does look at all aspect including your billing system. A good billing system like Modernbill will show your customers that you willing to invest in your company and also present a presence that their information, billing, and so on will be handled by a respectable system.

Another advantage of going with a system like Modernbill instead of a free billing system is the amount of extra features that will come in handy. Also the automation that you can get with this system will save you lots of time and work that could be used for other things.

Like they say "It takes money to make money".