This is topical. I have one small account that works like clockwork, and another larger one that DID until a couple months ago. Three years we've worked from them, and they used to be fantastic.
They changed ownership a year ago, and our contact left the company. Recently took them ~100 days to pay. We suspended service. Our contact blew us off, ignored phone calls, and straight-up lied to us. Surprisingly, they finally paid.
The want us to sign the 2017 contract now, and we added a clause regarding late payment fees. They haven't responded to us in two weeks. I think we're done.
Why the Long story? They were always my GOOD example of and NSP. And look how that has gone. I've dealt with worse.
Listen to this forum: if you work for NSPs, CHARGE HIGH and read those contracts CAREFULLY! They will try to screw you.
One other company stipulated in the contract that we would be subject to a $50 penalty fee if we were 45 minutes late unless we notified the management 2 days in advance. Also, we had to use only products purchased from them. AND, we had to download their app and allow it to track us. Please note: they didn't provide any of this info before we submitted an estimate. Needless to say, we passed. But, be aware of what tricks they have up their sleeve before you submit a bid. And, unless you're desperate for work, just pass.